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Car Forum / Ford / Ford Explorer / August 2006Replace all tires for a flat one?
My tire (rear/passenger side) got flat and the dealer told me it can't be fixed for a safty reason. That's ok. However, he asked me to replace all tires in order to tune ABS and so forth cause it is 4WD(I know only a little about car). BTW, the car is a 2003 XLT. I bought this car last year and it is only less than 15K miles so far. Is that a reasonable solution? I appreciate your suggestions! He is just trying to sell you tires! The ABS system is not going to be affected by the mere 1/4 of tread gain on one tire. YOu have 4 ABS sensors each one working independently of the other. I don't know what tires you have now or the condition of such. But on my Explorer I have BF G's All terrain TA's the ones in the front right now, have 13/32 of tread the back have 15/32 tread yes they are only about 6 months old. So, is your dealer going to tell me that my ABS is out of tune because of 2/32 o tread difference. If he did I would get it in writing then take them to the better business. If your tires are down to less than 3/32 of tread depth then you should replace all of them. He may have said that it can't be fixed for saftey reasons because as a general rule most tire facilities will not repair a tire that is less than 3/32 of tread depth or the hole is within 3/4 of a sidewall. I hope this helps, But please don't beleive the ABS crap, thats a sales tactic meant to worry you into new tires. Much like telling a woman (my wife) that her brakes are wearing down. I looked at the brake pads to find over half of the of pad left, they were fine. But it was said in order to "SELL THE SAFTEY" issue. Searcher1 > My tire (rear/passenger side) got flat and the dealer told me it can't > be fixed for a safty reason. That's ok. However, he asked me to > replace all tires in order to tune ABS and so forth cause it is 4WD(I > know only a little about car). BTW, the car is a 2003 XLT. I bought > this car last year and it is only less than 15K miles so far. Is that > a reasonable solution? I appreciate your suggestions! > My tire (rear/passenger side) got flat and the dealer told me it can't > be fixed for a safty reason. That's ok. However, he asked me to > replace all tires in order to tune ABS and so forth cause it is 4WD(I > know only a little about car). BTW, the car is a 2003 XLT. I bought > this car last year and it is only less than 15K miles so far. Is that > a reasonable solution? I appreciate your suggestions! Your dealer is an "a.shole" Find a good/honest tire store and talk with them. Most of them will tell you what can/can't be safely repaired. I only go back to the dealer for factory recalls or defects. > > My tire (rear/passenger side) got flat and the dealer told me it can't > > be fixed for a safty reason. That's ok. However, he asked me to > > replace all tires in order to tune ABS and so forth cause it is 4WD(I > > know only a little about car). BTW, the car is a 2003 XLT. I bought > > this car last year and it is only less than 15K miles so far. Is that > > a reasonable solution? I appreciate your suggestions! What I would do is buy a new tire to match, take the spare which should be new and put that on. This way you have two new tires on the same axle. Then I use the other that had 15k on it for the spare. Janet Previously in rec.autos.makers.ford.explorer, Janet <maliu@ilhawaii.net> proclaimed : >> > My tire (rear/passenger side) got flat and the dealer told me it can't >> > be fixed for a safty reason. That's ok. However, he asked me to [quoted text clipped - 8 lines] > >Janet unfortunately, the dealer is correct. In a 4wd system, *all* tires must be replaced. The uneven tread depth that a new tire would can really mess up your 4x4 drive train. If you never put the vehicle in 4x4 then it isn't an issue. __________________________________________________________________________ People are more violently opposed to fur than leather because it's safer to harass rich women than motorcycle gangs. -Unknown __________________________________________________________________________ Remove "die spammers" to email >Previously in rec.autos.makers.ford.explorer, Janet ><maliu@ilhawaii.net> proclaimed : [quoted text clipped - 17 lines] > >If you never put the vehicle in 4x4 then it isn't an issue. Nope. The differential will take up any such minor differences in tire circunference. And since 4x4 should only be used when the tires can slip anyway, that's *really* not true.  SignatureBill Funk Change "g" to "a" Previously in rec.autos.makers.ford.explorer, Big Bill <bill@pipping.com> proclaimed : >>Previously in rec.autos.makers.ford.explorer, Janet >><maliu@ilhawaii.net> proclaimed : [quoted text clipped - 23 lines] >And since 4x4 should only be used when the tires can slip anyway, >that's *really* not true. this took all of 2 minutes to find. There's dozens of resources out there that say the same thing: http://www.tirerack.com/tires/tiretech/general/matchingtires.jsp __________________________________________________________________________ People are more violently opposed to fur than leather because it's safer to harass rich women than motorcycle gangs. -Unknown __________________________________________________________________________ Remove "die spammers" to email > this took all of 2 minutes to find. There's dozens of resources out > there that say the same thing: > > http://www.tirerack.com/tires/tiretech/general/matchingtires.jsp That's an interesting article but I fail to understand the actual theory behind their claim: "As an example of different tire diameters resulting from tires worn to different tread depths,..." "While the difference of 1/8" in overall diameter doesn't seem excessive, the resulting 4 revolutions per mile difference can place a continuous strain on the tires and vehicle's driveline. Obviously, the greater the difference in the tires' circumferences, the greater the resulting strain" In the above example, the difference in rotation at 60mph would amount to 4 rpm. If you have 4WD then the the front axle is disconnected from the driveline on the roadway anyway. If you have AWD then the transfer case is viscous coupled, which allows slippage between the front and rear axles. So difference in wear between front and rear axles is insignificant. If you have open diffs then the amount of difference in rotational speed between wheels on teh ame axle is also of no consequence. Even if you have limited slip diffs, slippage between two wheels on the same axle at 4 rpm is hardly anything compared to the amount of slippage that occurs normally when steering. I cannot see where this would put undue "strain" on anything. Obviously if you put a different sized tire on, or a different manufacturer the differences in circumference wiould be magnified and at some point *could* be significant. It sounds to me like this theory is in the best interest of tire merchants or services that perform "shaving" to match the diameters. I'd be interested in some hard evidence that shows a cause and effect relationship of worn driveline parts and slightly mismatched tires such as what one would expect from wear. -Fred W Thanks for posting this link, very interesting article. Also explains why Ford recommends rotating tires so often. >> this took all of 2 minutes to find. There's dozens of resources out >> there that say the same thing: [quoted text clipped - 38 lines] > >-Fred W Previously in rec.autos.makers.ford.explorer, Fred W <Fred.Wills@SPAMmyrealbox.com> proclaimed : >> this took all of 2 minutes to find. There's dozens of resources out >> there that say the same thing: [quoted text clipped - 3 lines] >That's an interesting article but I fail to understand the actual theory >behind their claim: <snip good comments> >It sounds to me like this theory is in the best interest of tire >merchants or services that perform "shaving" to match the diameters. [quoted text clipped - 4 lines] > >-Fred W It shouldn't take much time to do some searching on the net to substantiate the link I posted. I *do* know that I've been told by more than one reputable technician (one of which is Pat Goss, who hosts Goss' Garage radio show and has a segment on Motor Week), that he *most definitely* would NOT recommend a new tire replacement on a 4x4 unless the other three tires are almost new. He has absolutely no interest in selling tires btw. __________________________________________________________________________ People are more violently opposed to fur than leather because it's safer to harass rich women than motorcycle gangs. -Unknown __________________________________________________________________________ Remove "die spammers" to email So 4 RPM on one tire results in 2 RPM increase on the driveshaft for that end of the car. Is Control Trac so sensitive that it would trigger on a 2 rpm difference? Especially a difference that was present for a sustained amount of time. It would seem Ford would have to allow for long term differences in RPM from front to back. Engine computer does something similar with long term fuel trim doesn't it? >Previously in rec.autos.makers.ford.explorer, Big Bill ><bill@pipping.com> proclaimed : [quoted text clipped - 31 lines] > >http://www.tirerack.com/tires/tiretech/general/matchingtires.jsp Hmmm... I wonder what those differentials are there for? Tirerack, in case eyou missed it, sells tires. You don't think thety may have an ulterior motive, do you? Nah, couldn't be. Differentials are there for just such a purpose. We hardly ever drrive in a straight line, even on straight stretches of road. Check your own steereing wheel as you drive; it's constantly moving, making small adjustments, which makes the car turn. This makes the tires take different tracks, making them turn at different rates. That's why the differentials are there. 4X4 should not be used when the tires can't slip. Even lockers (which, BTW, lock not when power is applied, but when there's slippage betweent the tires on the same end). SignatureBill Funk Change "g" to "a" >> > My tire (rear/passenger side) got flat and the dealer told me it can't >> > be fixed for a safty reason. That's ok. However, he asked me to [quoted text clipped - 8 lines] > > Janet You are being lied to and taken advantage of. There is another solution to your problem. The ONLY reason I could see what the "dealer" is saying is if the other tires were worn and needed to be replaced anyway..but that is because it would make since to buy 4 new tires instead of buying one new and having 3 badly worn others. Is this the ford dealership or a tire dealer? What town are you in? If you have the spare still on shop around Monday..find a friend you trust to help you make your decision. Thanks, Sam in Raleigh. >>> > My tire (rear/passenger side) got flat and the dealer told me it can't >>> > be fixed for a safty reason. That's ok. However, he asked me to >>> > replace all tires in order to tune ABS and so forth cause it is 4WD(I >>> > know only a little about car). BTW, the car is a 2003 XLT. I bought >>> > this car last year and it is only less than 15K miles so far. Is that >>> > a reasonable solution? I appreciate your suggestions! Check the owner's manual for information about this. Some of the newer vehicles require that the tires all be the same diameter in order for the traction and stability control systems to work properly. My understanding is that a different size tire can be interpreted as wheel spin, causing 4WD to partially engage all the time. >You are being lied to and taken advantage of. There is another >solution to your problem. [quoted text clipped - 18 lines] >>>> > this car last year and it is only less than 15K miles so far. Is that >>>> > a reasonable solution? I appreciate your suggestions! All vehicles with computer controlled AWD must have all tires replaced at the same time. As discussed before, the newer tire will have a greater diameter and circumference and will in turn spin at a lesser rate than the other three tires. Greater diameter means less revs per mile. This will be interpreted as wheel spin by the computer and will engage the differentials. This will burn out the clutches in the diffs. There have been a lot of vehicles coming in for service that requires the replacement of the differentials. This is due to the computer keeping them engaged all the time and burning them out. This is why they are telling you to replace all four tires. He will note this in your maintenance log in the computer. If the vehicle comes in at a later date with burned out clutches in the diffs then they can and will deny you warranty coverage because it was not caused by normal wear and tear. You were advised and then failed to take the advice of the service technician. I have read all these horror stories on the Audi and VW forums. The Quattro AWD system has a service note in the manual informing the owner of this. The Quattro system isn't computer controlled. I've been working for VW/Audi and owned various Quattros throughout the past 20 years and still do. I have never heard of any differential clutch damage in a Quattro. In fact it would be a remarkable incident, since the Quattro differentials don't have a clutch. A clutch is only used in non full time 4WD's. The VW Syncro system works with a visco-clutch, a system that can't be compared to control trac anyway. There are way too many Volkswagens around here, which have different wheel dimensions on the front and rear axle that this damage theory could hold. Beside, I spent much time in German Quattro forums and never read one single "horror story" like this... > All vehicles with computer controlled AWD must have all tires replaced at > the same time. As discussed before, the newer tire will have a greater [quoted text clipped - 15 lines] > Quattro AWD system has a service note in the manual informing the owner of > this. If you look at tirerack.com they actually offer a "tire shaving service." Check out: http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=18 > All vehicles with computer controlled AWD must have all tires replaced at > the same time. As discussed before, the newer tire will have a greater [quoted text clipped - 15 lines] > Quattro AWD system has a service note in the manual informing the owner of > this. Interesting article, makes sense to me. >If you look at tirerack.com they actually offer a "tire shaving service." >Check out: [quoted text clipped - 19 lines] >> Quattro AWD system has a service note in the manual informing the owner of >> this. > My tire (rear/passenger side) got flat and the dealer told me it can't > be fixed for a safty reason. That's ok. However, he asked me to > replace all tires in order to tune ABS and so forth cause it is 4WD(I > know only a little about car). BTW, the car is a 2003 XLT. I bought > this car last year and it is only less than 15K miles so far. Is that > a reasonable solution? I appreciate your suggestions! We had a similar situation on our Sport Trac at about 20000 miles. The dealer suggested putting the new spare on in place of the cut tire. (Tire was cut, but not clear through). That's what we did and have had no problems with ABS or 4wd. I think your dealer just wants to sell tires. H Absolute claptrap. Get yourself a new and HONEST dealer. It doesnot work that way.... > My tire (rear/passenger side) got flat and the dealer told me it can't > be fixed for a safty reason. That's ok. However, he asked me to > replace all tires in order to tune ABS and so forth cause it is 4WD(I > know only a little about car). BTW, the car is a 2003 XLT. I bought > this car last year and it is only less than 15K miles so far. Is that > a reasonable solution? I appreciate your suggestions! If you have a locking rear end, you should have the same sized and brand of tires with similar tread wear on both sides. Because, different sized tires will greatly increase the wear and tear on your locking assembly (clutches) because the tires are unable to spin at the same rate. If you have a 4x4 It is great practice to keep the same sized and brand of tires with similar tread wear on all 4 corners. I always do, But unless it is full time 4x4, or you are in the habit of running around in four wheel drive on dry pavement, it really is not that critical as long as the new tire is the same sized and brand as the other 3. If you have the locking rear end, make sure you have two "matching" on the rear axel. I have owned and driven 4x4 Ford trucks and Bronco's for 25 years. I always replace my tires in sets of 4, (the newest truck will be sets of 6 :-0) the only time I have lost a tire to a catastrophic failure and have not had all 4 tires last the life of the set, was when I punched 2 separate sidewalls on two consecutive weekends on a fairly new set of tires. These tires were purchased from Les Schwab tires, a regional North West dealer who has offered full on and off road, unlimited warranty which covers sidewall punctures since I have been driving, they replaced both for free. If you are not running around on dry pavement in four wheel drive, have the single new tire of the same brand and size put on the front and you will be fine. Good Luck >> My tire (rear/passenger side) got flat and the dealer told me it can't >> be fixed for a safty reason. That's ok. However, he asked me to [quoted text clipped - 7 lines] >will greatly increase the wear and tear on your locking assembly (clutches) >because the tires are unable to spin at the same rate. A locking rear end should not be locked unless traction is poor enough to allow the tires to slip. This means that even with the diff locked, a minor difference in tire circumference won't matter. >If you have a 4x4 It is great practice to keep the same sized and brand of >tires with similar tread wear on all 4 corners. I always do, But unless it >is full time 4x4, or you are in the habit of running around in four wheel >drive on dry pavement, it really is not that critical as long as the new >tire is the same sized and brand as the other 3. If you have the locking >rear end, make sure you have two "matching" on the rear axel. Yes, same brand and size. But tire size is nominal; small differences occur within the same model. Ever see race teams measure their tires with an eye to placing the different sizes on different corners to improve handling? And these are racing tires; hand made, to be as uniform as possible. Tires bought 'off the rack', so to speak, are not identical. See above for the locking rear end thing. >I have owned and driven 4x4 Ford trucks and Bronco's for 25 years. I always >replace my tires in sets of 4, (the newest truck will be sets of 6 :-0) the [quoted text clipped - 8 lines] >single new tire of the same brand and size put on the front and you will be >fine. Why would anyone run around in four wheel drive on dry pavement? 25 years? Not to sound like I'm making fun of you, but your post does not reflect the experience of four-wheeling for 25 years. >Good Luck SignatureBill Funk Change "g" to "a" > >> My tire (rear/passenger side) got flat and the dealer told me it can't > >> be fixed for a safty reason. That's ok. However, he asked me to [quoted text clipped - 11 lines] > to allow the tires to slip. This means that even with the diff locked, > a minor difference in tire circumference won't matter. BULLSHIT! Obviously you have Zero experience with locking rearends. They lock according to the TORQUE being applied to them. They have ZERO input as to the condition of the traction!!! You stomp the gas both axels are locked and driven, regardless of traction conditions. DUH! I currently have Four 4x4's and 3 cars that have locking rearends. I have rebuilt and set up more rearends then you have owned in your lifetime. I have worn out, twisted 31 spine axels, stripped the axel splines off and even grenaded a couple Ford 9 inch rearends. I have a thorough understanding of the design and function from the inside out. If you are going to correct someone you really ought to understand what the hell you are talking about... > >If you have a 4x4 It is great practice to keep the same sized and brand of > >tires with similar tread wear on all 4 corners. I always do, But unless it [quoted text clipped - 26 lines] > Why would anyone run around in four wheel drive on dry pavement? > 25 years? Duh! I don't, know, maybe they are driving a FULL-TIME 4x4, or who knows, but my point was, since the vast majority of 4x4's never drive around in four wheel drive on dry pavement, there would be no issues... Do you just generally have trouble with reading comprehension? > Not to sound like I'm making fun of you, but your post does not > reflect the experience of four-wheeling for 25 years. Your comments reflect embarrassing mechanical & reading comprehension... No number of years is likely to correct that... > >Good Luck > > -- > Bill Funk > Change "g" to "a" >> >> My tire (rear/passenger side) got flat and the dealer told me it can't >> >> be fixed for a safty reason. That's ok. However, he asked me to [quoted text clipped - 92 lines] >> Bill Funk >> Change "g" to "a" >> >> My tire (rear/passenger side) got flat and the dealer told me it can't >> >> be fixed for a safty reason. That's ok. However, he asked me to [quoted text clipped - 92 lines] >> Bill Funk >> Change "g" to "a" No experience with lockers, well I do. And you are wrong sir, the difference in tread depth is not going to effect the persons OR your lockers to the point of a problem. Tread depth is 15/32 (NEW BFGAT) after 15000 miles even these tires are not going to drop to any less than 10/32, So now if you are telling me that 5/32 of tire difference is going to effect your lockers then you need to go out and buy you a set of ARB's. THe only things that should be of concern are speed rating, tire size, not even brand really makes a hoo haa. Searcher1 >> >> My tire (rear/passenger side) got flat and the dealer told me it can't >> >> be fixed for a safty reason. That's ok. However, he asked me to [quoted text clipped - 92 lines] >> Bill Funk >> Change "g" to "a" >> >> My tire (rear/passenger side) got flat and the dealer told me it can't >> >> be fixed for a safty reason. That's ok. However, he asked me to [quoted text clipped - 20 lines] >the condition of the traction!!! You stomp the gas both axels are locked and >driven, regardless of traction conditions. DUH! And, pray tell, on pavement, how much time does your locker spend locked? Use a little common sense. >I currently have Four 4x4's and 3 cars that have locking rearends. I have >rebuilt and set up more rearends then you have owned in your lifetime. I [quoted text clipped - 60 lines] >> Bill Funk >> Change "g" to "a" SignatureBill Funk Change "g" to "a" > >> >> My tire (rear/passenger side) got flat and the dealer told me it can't > >> >> be fixed for a safty reason. That's ok. However, he asked me to [quoted text clipped - 24 lines] > locked? > Use a little common sense. Generally every time you take off with more then 1/4 throttle... That for many drivers is every time the start from a stand still. If you are going to correct someone you really ought to understand what the hell you are talking about... > >I currently have Four 4x4's and 3 cars that have locking rearends. I have > >rebuilt and set up more rearends then you have owned in your lifetime. I [quoted text clipped - 65 lines] > Bill Funk > Change "g" to "a" >> >> >> My tire (rear/passenger side) got flat and the dealer told me it >can't [quoted text clipped - 32 lines] >Generally every time you take off with more then 1/4 throttle... >That for many drivers is every time the start from a stand still. Your tires slip with 1/4 throttle? >If you are going to correct someone you really ought to understand what the >hell you are talking about... Why would the diff need to lock at such low power? Do you oil your tires? SignatureBill Funk Change "g" to "a" > >> >> >> My tire (rear/passenger side) got flat and the dealer told me it > >can't [quoted text clipped - 40 lines] > Why would the diff need to lock at such low power? Do you oil your > tires? Don't be a blockhead, they do not LOCK from slippage, they lock from Torque.... Duh! Stop by I'll demonstrate it to you... Here I'll repost this since you seam incapable of following the thread. The most common limited slip differentials found in performance cars and trucks are of the cone or clutch type. Many cone or clutch type differentials use preload springs to help keep some tension on the unit at all times. There is torque applied to both axels, not just when there is slippage. Limited Slips: (LSD's) come in a variety of designs. Most use friction plates, cones and/or gears to reduce slippage between each of the tires. these units have a dual power path from the differential case to the axle shafts. some power is transmitted through the spider gears to the side gears in the conventional manner. The remainder is transmitted by friction between the differential case and the clutch plates and the side gears. A certain amount of "clutch preload" is built into the unit in a static condition. Then, as load is applied to the differential, the separation forces between the spider gears and the side gears increases this clutch loading. This increase in friction provides for a good positive power flow from the case directly to the side gears. When traction is available to both wheels, the power going to the differential causes the plates to bind tightly together, giving even power to both wheels. However, in a situation where there is little or no traction available to either one wheel or the other, the amount of power that can be transmitted to the other wheel which has traction is dependent on the friction or "preload" in the clutch plates. High levels of "clutch preload" will result in good torque transfer but some chattering of the clutches during cornering may occur. Lower levels of preload results in minimal chatter but reduced levels of torque transfer to the wheel with traction. Because LSD's restrict true differential action, tire wear is accelerated. Changes in vehicle handling may also occur, particularly in short wheelbase vehicles. Wear rates on limited slip differentials are generally higher than on other types due to the reliance on friction to reduce wheel slippage. Also, special lubricants may be required to minimize rough and noisy operation. http://www.therangerstation.com/tech_library/LockerComparo.html I realize your being stuck in this funk may be genetic, pun intended, but please do try to follow along. > -- > Bill Funk > Change "g" to "a" >> >> >> >> My tire (rear/passenger side) got flat and the dealer told me it >> >can't [quoted text clipped - 92 lines] >I realize your being stuck in this funk may be genetic, pun intended, but >please do try to follow along. OK, put on your thinking cap here... If the diff is locked, how does the diff allow differential speeds betweent he wheels on turns under power? Answer: they aren't locked. So then, how do these things actually work? Answer: they sense the slippage beyond a preset amount,and then lock. This doesn't happen under normal accelleration. SignatureBill Funk Change "g" to "a" >> >> >> My tire (rear/passenger side) got flat and the dealer told me it >can't [quoted text clipped - 32 lines] >Generally every time you take off with more then 1/4 throttle... >That for many drivers is every time the start from a stand still. Please explain the mechanism that would cause this. On pavement, 1/4 throttle won't cause any difference in tire slip between the two tires. No differential (between sides) slip = no lockup in any "Locking axle" I've driven. So how do you figure they lock up?? >If you are going to correct someone you really ought to understand what the >hell you are talking about... [quoted text clipped - 83 lines] >> Bill Funk >> Change "g" to "a" -- Elbridge Gerry, of Massachusetts: "What, sir, is the use of militia? It is to prevent the establishment of a standing army, the bane of liberty. . . Whenever Government means to invade the rights and liberties of the people, they always attempt to destroy the militia, in order to raise a standing army upon its ruins." -- Debate, U.S. House of Representatives, August 17, 1789 > >> >> >> My tire (rear/passenger side) got flat and the dealer told me it > >can't [quoted text clipped - 37 lines] > tires. No differential (between sides) slip = no lockup in any > "Locking axle" I've driven. So how do you figure they lock up?? Do you have any clue how the clutch pack in a factory ford "locking" rear end works, or even a conventional mechanical Detroit locker? Cause you question doesn't indicate that you do... Ford sells a Trac-Lok clutch-plate limited slip differential as a locking differential, although it is not a true locker. They do not offer a true locker, you would have to install or have that installed yourself. So if you order you truck from Ford with a "locking differential", you really have a Trac-Lok clutch-plate limited slip differential. A conventional open differential sends equal amounts of torque to both axle shafts. If one wheel spins because of lost traction, it is sustaining zero engine torque, so zero engine torque is also going to the wheel with traction. The most common limited slip differentials found in performance cars and trucks are of the cone or clutch type. Many cone or clutch type differentials use preload springs to help keep some tension on the unit at all times. There is torque applied to both axels, not just when there is slippage. Limited Slips: (LSD's) come in a variety of designs. Most use friction plates, cones and/or gears to reduce slippage between each of the tires. these units have a dual power path from the differential case to the axle shafts. some power is transmitted through the spider gears to the side gears in the conventional manner. The remainder is transmitted by friction between the differential case and the clutch plates and the side gears. A certain amount of "clutch preload" is built into the unit in a static condition. Then, as load is applied to the differential, the separation forces between the spider gears and the side gears increases this clutch loading. This increase in friction provides for a good positive power flow from the case directly to the side gears. When traction is available to both wheels, the power going to the differential causes the plates to bind tightly together, giving even power to both wheels. However, in a situation where there is little or no traction available to either one wheel or the other, the amount of power that can be transmitted to the other wheel which has traction is dependent on the friction or "preload" in the clutch plates. High levels of "clutch preload" will result in good torque transfer but some chattering of the clutches during cornering may occur. Lower levels of preload results in minimal chatter but reduced levels of torque transfer to the wheel with traction. Because LSD's restrict true differential action, tire wear is accelerated. Changes in vehicle handling may also occur, particularly in short wheelbase vehicles. Wear rates on limited slip differentials are generally higher than on other types due to the reliance on friction to reduce wheel slippage. Also, special lubricants may be required to minimize rough and noisy operation. http://www.therangerstation.com/tech_library/LockerComparo.html > >If you are going to correct someone you really ought to understand what the > >hell you are talking about... [quoted text clipped - 93 lines] > to raise a standing army upon its ruins." -- Debate, U.S. House > of Representatives, August 17, 1789 >> >> >> >> My tire (rear/passenger side) got flat and the dealer told me it >> >can't [quoted text clipped - 91 lines] > >http://www.therangerstation.com/tech_library/LockerComparo.html But you didn't answer the question. Why would a 1/4 throttle accelleration cause your tires to slip? I know I understand how diffs work; I'm just not sure why *your* diffs lock under 1/4 throttle accelleration on pavement. SignatureBill Funk Change "g" to "a" > >> >> >> >> My tire (rear/passenger side) got flat and the dealer told me it > >> >can't [quoted text clipped - 96 lines] > I know I understand how diffs work; I'm just not sure why *your* diffs > lock under 1/4 throttle accelleration on pavement. Just because you have a reading comprehension problem DOES Not mean I don't know what I am talking about or how to explain it... Generally every time you take off with more than 1/4 throttle... That for many drivers is every time the start from a stand still. The key here is "more than 1/4 throttle". Duh... > -- > Bill Funk > Change "g" to "a" >> >> >> >> >> My tire (rear/passenger side) got flat and the dealer told me >it [quoted text clipped - 129 lines] > >The key here is "more than 1/4 throttle". Duh... I understand exactly how the different types of differentials work. You have not explained in anyway why a locking diff would "lock" under conditions that do not cause one of the wheels to slip relative to the other. If you can't answer that just say so. Your saying "..it locks.." is not an explanation of why you think it locks. There is zero reason for it to lock (or for the clutch pack in a LSD to "engage") under the conditions being discussed, whether at 1/5 throttle or 2/3rds throttle) so I'd like to know what makes you think it would lock. I've taken off many times in Chevy's with Eaton lockers on pavement at full throttle without the diff locking. Conversely, the same truck on loose gravel might lock at less then quarter throttle if started on loose gravel while turning. -- Elbridge Gerry, of Massachusetts: "What, sir, is the use of militia? It is to prevent the establishment of a standing army, the bane of liberty. . . Whenever Government means to invade the rights and liberties of the people, they always attempt to destroy the militia, in order to raise a standing army upon its ruins." -- Debate, U.S. House of Representatives, August 17, 1789 > >> >> >> >> >> My tire (rear/passenger side) got flat and the dealer told me > >it [quoted text clipped - 151 lines] > to raise a standing army upon its ruins." -- Debate, U.S. House > of Representatives, August 17, 1789 What the hell makes you think it is not locked??? Unless you are spinning one tire on pavement and not the other, at full throttle without the differential locking, in which case you are describing that your limited slip differential is not functioning properly. Just because you are not losing traction (spinning your tire(s)) ABSOLUTELY DOES NOT INDICATE THAT THE LOCKING MECHANISM IS NOT LOCKED or that you are not applying power to both axels!!! On the other hand it may simply be that you don't have enough power to spin either of your tires on dry pavement, let alone both of them... The whole idea is for the locking differential to drive both axels and avoid one or the other of them from having to slip... The limited slip information I posted in my other posts was not what I said it was on a web page I have nothing to do with... http://www.therangerstation.com/tech_library/LockerComparo.html in the Limited Slip section, I included the link so you can read it yourself... It is real easy for you to check yourself provided you have access to a working limited slip differential. If you jack both wheels off the ground and spin one axel one way the other axel will spin that way too! As matter of fact, if you ask a friend to hold one axel while you spin the other they will not move separately. this is the no-load no-slippage PRELOAD that is always being applied. This connection between the two axels never gets any less than in that neutral state, unless enough torque is applied to break the grip of the clutch. When torque is applied the clutch grips harder yet. FYI: If you don't know it, a standard OPEN differential if jacked up and one axel is spun, the other axel will spin the opposite direction. If you still can't understand it take a class. >What the hell makes you think it is not locked??? >Unless you are spinning one tire on pavement and not the other, at full [quoted text clipped - 29 lines] > >If you still can't understand it take a class. I think I see the problem here. You're assuming the the diff is locked becasue you don't experience tire spin. Not true. That's not the way they work. They lock when they sense the different rates of spin on the different axle shafts. Otherwise, the diff would remain locked even around turns, which is not a good thing. SignatureBill Funk Change "g" to "a" >> >> >> >> >> On Sun, 05 Dec 2004 23:28:24 GMT, "351CJ" <351CJ@MSN.com> >wrote: [quoted text clipped - 188 lines] > >What the hell makes you think it is not locked??? Because I know how they work. They don't lock when there is no differential wheel rotation because there is no need to lock. >Unless you are spinning one tire on pavement and not the other, at full >throttle without the differential locking, in which case you are describing [quoted text clipped - 28 lines] > >If you still can't understand it take a class. -- Elbridge Gerry, of Massachusetts: "What, sir, is the use of militia? It is to prevent the establishment of a standing army, the bane of liberty. . . Whenever Government means to invade the rights and liberties of the people, they always attempt to destroy the militia, in order to raise a standing army upon its ruins." -- Debate, U.S. House of Representatives, August 17, 1789 >> But you didn't answer the question. >> Why would a 1/4 throttle accelleration cause your tires to slip? [quoted text clipped - 8 lines] > >The key here is "more than 1/4 throttle". Duh... I have to admit that what you're saying defys my knowledge of how diffs work, and the nortmal physics of vehicle accelleration. Why does accelleration of *more than* 1/4 throttle lock the diff? What's slipping? Do your vehicles all spin tires at 1/2 throttle accelleration? SignatureBill Funk Change "g" to "a" > >> But you didn't answer the question. > >> Why would a 1/4 throttle accelleration cause your tires to slip? [quoted text clipped - 18 lines] > Bill Funk > Change "g" to "a" Yes, my slouchiest is a 3/4 ton 4x4 with a 460 5 speed, and it spins the tires at far under 1/2 throttle. All of my Ford cars with Traction Loc's can spin the tires in all gears, and easily in 1st at well under 1/2 throttle. Even the wife's Toyota Camry 3.0L 5 speed spins its tires if you don't try not to... >> >> But you didn't answer the question. >> >> Why would a 1/4 throttle accelleration cause your tires to slip? [quoted text clipped - 25 lines] >throttle. Even the wife's Toyota Camry 3.0L 5 speed spins its tires if you >don't try not to... That's rather amazing. I think I now undertstand where you're coming from. I always tried to keep decent tires on my vehicles so that didn't happen. I do think tho that you might want to reconside your thoughts on diff locks; they lock on a speed differential between the wheels, not on power. The fact that *your* vehicles spin their tires so easily is not characteristic of other vehicles. SignatureBill Funk Change "g" to "a" |
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