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Car Forum / Dodge / Dodge Trucks / August 2006Trans Shifting Problem.
Hi all,98 Ram 1500,5.9 4x4 Quad Cab.90715 miles. For the past week,it has started shifting later than it used to,and a couple of times wouldnt shift out of first unless I let off the gas,then it shifted with up through the gears. When this happened,I just got off the freeway,pulling away from a stop sign. It hanging on longer to shift.Any ideas ,and suggestions would be appreciated. Thanks. elowejr@webtv.net >Hi all,98 Ram 1500,5.9 4x4 Quad Cab.90715 miles. For the past week,it >has started shifting later than it used to,and a couple of times wouldnt [quoted text clipped - 3 lines] >ideas ,and suggestions would be appreciated. Thanks. >elowejr@webtv.net Shift point are linked to engine performance (manifold pressure) and if engine is lagging a bit it will delay shifts. Maybe you should start with a fresh tuneup and oil change and if that fails try better fuel (higher octane) in hot weather. Also if you have oversized tires this throughs things of too which many do not realize. ----------------- TheSnoMan.com Huh? Larry Behold Beware Believe >> <<snip>> >> [quoted text clipped - 9 lines] > ----------------- > TheSnoMan.com  SignaturePosted via a free Usenet account from http://www.teranews.com I guess that "of" missing a second "F" for off realy confused you. >Huh? > [quoted text clipped - 14 lines] >> ----------------- >> TheSnoMan.com ----------------- TheSnoMan.com > Shift point are linked to engine performance (manifold pressure) and > if engine is lagging a bit it will delay shifts. Shift points are determined by more than just engine performance. Many inputs are taken by the PCM and used to determine transmission shift points. > Maybe you should > start with a fresh tuneup and oil change and if that fails try better > fuel (higher octane) in hot weather. A tune up might help, but not likely. An oil change will do nothing for the shift points. Better fuel won't change shift points. > Also if you have oversized tires > this throughs things of too which many do not realize. Oversize tires won't make a difference from one day to the next, unless its the day you install or remove them. First step would be to check the PCM for codes. Since its a 98, you'll need to have it scanned for these codes. Second might be to change filter and fluid in the trans and put a new set of solenoids for the governor pressure sensor and transducer. SignatureMax Join www.devilbrad.com and find out what free exchange of info is all about. "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) >>Hi all,98 Ram 1500,5.9 4x4 Quad Cab.90715 miles. For the past week,it >>has started shifting later than it used to,and a couple of times wouldnt [quoted text clipped - 11 lines] > ----------------- > TheSnoMan.com >Shift points are determined by more than just engine performance. Many >inputs are taken by the PCM and used to determine transmission shift points. Not really, road speed and engine load and load is primarily used and it is calculated by RPM and manifold pressure (as this is a measure on engine output against speed/load, throttle position play a roll but only realeted to the resulting manifold pressure) When a engine is out of tune, it will have a higher manifold pressure (lower vacum) at a given speed than one that is in good tune so the shift will delay or hang whether it is a Dodge, Chevy or Ford. And as mentioned earier if it has oversized tires this increases the effort required by a untuned engine (as well as a tuned one) and it can change shift points as well. ----------------- TheSnoMan.com > Not really, road speed and engine load and load is primarily used and > it is calculated by RPM and manifold pressure (as this is a measure on > engine output against speed/load, throttle position play a roll but > only realeted to the resulting manifold pressure) Um, no. According to the 2000 FSM, inputs to the governor control come from Fluid temp TPS speed sensor Gov pressure sensor PCM Gov pressure solenoid valve Notice that this list has no MAP sensor or tach signal. > When a engine is out > of tune, it will have a higher manifold pressure (lower vacum) at a > given speed than one that is in good tune so the shift will delay or > hang whether it is a Dodge, Chevy or Ford. More false info. Vacuum is a factor of RPM vs throttle position. state of tune is irrelevant unless mechanical problems are present in the valvetrain. > And as mentioned earier if > it has oversized tires this increases the effort required by a untuned > engine (as well as a tuned one) and it can change shift points as > well. Correct, but the state of tune would have to be drastically degraded to have a change in shift point, no something that generally happens overnight. SignatureMax Join www.devilbrad.com and find out what free exchange of info is all about. "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) >>Shift points are determined by more than just engine performance. Many >>inputs are taken by the PCM and used to determine transmission shift [quoted text clipped - 12 lines] > ----------------- > TheSnoMan.com >More false info. Vacuum is a factor of RPM vs throttle position. state of >tune is irrelevant unless mechanical problems are present in the valvetrain. Max Dodges Max crap. Engine tune HAS EVERYTHING to do with it because a detuned engine requires more throttle for the same output. but I guess the escapes him. I will be he believes rolling resistance has no effect either. ----------------- TheSnoMan.com >>More false info. Vacuum is a factor of RPM vs throttle position. state of >>tune is irrelevant unless mechanical problems are present in the valvetrain. [quoted text clipped - 5 lines] > ----------------- > TheSnoMan.com Huh? > Max Dodges Max crap. Engine tune HAS EVERYTHING to do with it because > a detuned engine requires more throttle for the same output. While you are correct that a detuned engine may require more throttle, the PCM isn't looking for just TPS or just RPM. As such, the state of engine tune has little effect since the TPS and RPM inputs vary independent of one another. This produces an infinite number of possible combinations that the PCM would see. That infinite number of combinations is possible with or without a well tuned engine. > but I > guess the escapes him. I see your claim that MAP had anything to do directly with trans shift points has now escaped you. > I will be he believes rolling resistance has no effect either. Certainly it has an effect, BUT.... we still don't know the size of the tires. What we can bet on is that the size of the tires didn't change from when the trans shifted correctly to when it started shifting incorrectly. Thus rolling resistance probably hasn't changed all that much, at least not suddenly as the OP seems to feel his trans did. SignatureMax Join www.devilbrad.com and find out what free exchange of info is all about. "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) >>More false info. Vacuum is a factor of RPM vs throttle position. state of >>tune is irrelevant unless mechanical problems are present in the [quoted text clipped - 6 lines] > ----------------- > TheSnoMan.com >> Max Dodges Max crap. Engine tune HAS EVERYTHING to do with it because >> a detuned engine requires more throttle for the same output. [quoted text clipped - 5 lines] > that the PCM would see. That infinite number of combinations is possible > with or without a well tuned engine. You're forgetting the TV cable, a large throttle input at low road speed is the classic scenario for a delayed upshift. > You're forgetting the TV cable, a large throttle input at low road speed > is the classic scenario for a delayed upshift. Not forgetting it at all. If the TV cable were out of adjustment, it would happen all the time, not just select incidents, as the OP infers. Second, it wouldn't happen suddenly, as the OP mentions, unless something broke and then the problem would be constant, not selective. Further, if the cable broke or stretched, the shifts would be too soon. Sorry, I'll stick to checking codes, then looking for physical damage. SignatureMax Join www.devilbrad.com and find out what free exchange of info is all about. "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) >>> Max Dodges Max crap. Engine tune HAS EVERYTHING to do with it because >>> a detuned engine requires more throttle for the same output. [quoted text clipped - 8 lines] > You're forgetting the TV cable, a large throttle input at low road speed > is the classic scenario for a delayed upshift. >> You're forgetting the TV cable, a large throttle input at low road speed >> is the classic scenario for a delayed upshift. [quoted text clipped - 4 lines] > and then the problem would be constant, not selective. Further, if the > cable broke or stretched, the shifts would be too soon. As usual you're missing my point, I'm not saying the TV cable is out of adjustment, I'm saying there is a possibility that a sick motor would require more throttle and more throttle means more TV cable extension; the overextended TV cable would delay the upshift. I'm not missing your point John. Infact, I've agreed that a sick motor could cause that effect. However, the OP made no mention of a sick motor, and claims the problem isn't always present, at least not to the same degree of severity. I'm not sure just how bad the engine would have to be for it to affect TV operation as severely as has been described, but its a fair guess its gotta be bad enough to notice more than a bad shift point. Further, since the OP noticed it in the last week, its also a fair bet its a noticable change, not a gradual one such as an out of tune engine. Again, I'd check codes first, and go from there. SignatureMax Join www.devilbrad.com and find out what free exchange of info is all about. "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) >>> You're forgetting the TV cable, a large throttle input at low road speed >>> is the classic scenario for a delayed upshift. [quoted text clipped - 9 lines] > require more throttle and more throttle means more TV cable extension; the > overextended TV cable would delay the upshift. > However, the OP made no mention of a sick motor, As I stated earlier, the operator might not be aware of a sick motor especially if there is no obvious misfiring, etc. And as I stated earlier, poor performance of the negine would have to be fairly serious to change a shift point to the degree the OP described. SignatureMax Join www.devilbrad.com and find out what free exchange of info is all about. "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) >> However, the OP made no mention of a sick motor, > > As I stated earlier, the operator might not be aware of a sick motor > especially if there is no obvious misfiring, etc. > > Not really, road speed and engine load and load is primarily used and > > it is calculated by RPM and manifold pressure (as this is a measure on [quoted text clipped - 11 lines] > > Notice that this list has no MAP sensor or tach signal. And what exactly is the PCM basing its input on? How about engine load and it determins that baced on the MAP, TPS, and RPM of the engine. > > When a engine is out > > of tune, it will have a higher manifold pressure (lower vacum) at a [quoted text clipped - 3 lines] > More false info. Vacuum is a factor of RPM vs throttle position. state of > tune is irrelevant unless mechanical problems are present in the valvetrain. LOL, you really do like making a fool out of yourself, don't you? How do you make an out of tune engine deliver the same amount of power? How about stepping on the gas a little harder and what happens when you do that? ANSWER: For a given RPM, that means that the throttle is opened more and the vacuum is LESS. So while you are correct on throttle position in relation to RPM, you seem to have no concept on what is can effect it.. > > And as mentioned earier if > > it has oversized tires this increases the effort required by a untuned [quoted text clipped - 3 lines] > Correct, but the state of tune would have to be drastically degraded to have > a change in shift point, no something that generally happens overnight. Really??? What if the cap cracks or an injector hangs or fails the regulator in the fuel pump goes bad or a sensor fails. All of these things can happen in an instant. SignatureIf at first you don't succeed, you're not cut out for skydiving > And what exactly is the PCM basing its input on? How about engine load > and > it determins that baced on the MAP, TPS, and RPM of the engine. Um, no. It determines shift points based on RPM TPS and input from the governor pressure sensor. Remember that list I posted? No? Here: >> Fluid temp >> TPS >> speed sensor >> Gov pressure sensor >> PCM >> Gov pressure solenoid valve You'll notice that the MAP sensor isn't on there. Notice also that ALL of those inputs go to the PCM. So if all the inputs go to the PCM, they could say that the PCM determines shift points. But they listed the inputs that the PCM uses to shift the trans, and MAP isn't one of them. > LOL, you really do like making a fool out of yourself, don't you? How do > you make an out of tune engine deliver the same amount of power? How [quoted text clipped - 3 lines] > the vacuum is LESS. So while you are correct on throttle position in > relation to RPM, you seem to have no concept on what is can effect it.. How well the engine is tuned has very little to do with RPM and throttle position when looking at vacuum. Those two variables are what determine vacuum in the engine. Not the sparkplugs, or the plug wires, or the cap and rotor, or the coil, or coil packs. None of those change vacuum. If you want to argue that TPS signal is changed, thats true, and I'd agree, but lets look at something.... > Hi all,98 Ram 1500,5.9 4x4 Quad Cab.90715 miles. For the past week,it > has started shifting later than it used to,and a couple of times wouldnt > shift out of first unless I let off the gas,then it shifted with up > through the gears. When this happened,I just got off the > freeway,pulling away from a stop sign. It hanging on longer to shift.Any > ideas ,and suggestions would be appreciated. Thanks. Clearly he is describing a problem that has to do with PCM control of the trans, NOT a change in tire size, or a poorly tuned motor (no mention of sluggishness). Furthermore, the problems he describes have been attributed to the governor pressure sensor and the governor pressure transducer. Thus, we're not looking at a tune up, we're looking at pulling the codes and seeing what the PCM has to say. > First step would be to check the PCM for codes. Since its a 98, you'll > need > to have it scanned for these codes. Second might be to change filter and > fluid in the trans and put a new set of solenoids for the governor > pressure > sensor and transducer. Interesting, since thats the first thing I mention doing. >> Correct, but the state of tune would have to be drastically degraded to > have >> a change in shift point, no something that generally happens overnight. > Really??? Really. > What if the cap cracks or an injector hangs or fails It causes a misfire, something that might be a bit more noticable than shift points. the > regulator in the fuel pump goes bad Poor engine operation would result, but the OP doesn't mention that. > or a sensor fails. All of these things > can happen in an instant. Wow, a sensor fails.... what was it that I said to check? Oh yeah.... > First step would be to check the PCM for codes. Since its a 98, you'll > need > to have it scanned for these codes. Second might be to change filter and > fluid in the trans and put a new set of solenoids for the governor > pressure > sensor and transducer. Just full of relevant info today, aren't you? SignatureMax Join www.devilbrad.com and find out what free exchange of info is all about. "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) >> > Not really, road speed and engine load and load is primarily used and >> > it is calculated by RPM and manifold pressure (as this is a measure on [quoted text clipped - 47 lines] > things > can happen in an instant. > > And what exactly is the PCM basing its input on? How about engine load > > and [quoted text clipped - 9 lines] > >> PCM > >> Gov pressure solenoid valve Yes Max, I remember and your list includes the PCM and if the PCM is controlling the shift points, why is it mentioned as an input? > You'll notice that the MAP sensor isn't on there. Notice also that ALL of > those inputs go to the PCM. So if all the inputs go to the PCM, they could > say that the PCM determines shift points. But they listed the inputs that > the PCM uses to shift the trans, and MAP isn't one of them. But they included the PCM itself as said above. Why do you think that is??? Perhaps because engine load is also a factor determined by the PCM and there is no need to further complicate matters by including all of the sensors and inputs that the PCM uses to determine engine load. > > LOL, you really do like making a fool out of yourself, don't you? How do > > you make an out of tune engine deliver the same amount of power? How [quoted text clipped - 6 lines] > How well the engine is tuned has very little to do with RPM and throttle > position when looking at vacuum. That is just about the dumbest thing to come out of you so far. It has everything to do with it when the engine is under load. > Those two variables are what determine > vacuum in the engine. Not the sparkplugs, or the plug wires, or the cap and > rotor, or the coil, or coil packs. None of those change vacuum. They don't change the engine vacuum in relation to throttle position but they do effect the amount of power the engine can deliver at specific throttle position which means to recover the lost power at the same RPM the throttle needs to be opened further which increases manifold pressure. > If you want to argue that TPS signal is changed, thats true, and I'd agree, > but lets look at something.... What exactly are we going to look at Max. By saying the TPS signal will change only proves that the manifold pressure will also change for a given RPM which basically is you saying that YOU are incorrect in your previous statement. > > Hi all,98 Ram 1500,5.9 4x4 Quad Cab.90715 miles. For the past week,it > > has started shifting later than it used to,and a couple of times wouldnt [quoted text clipped - 9 lines] > we're not looking at a tune up, we're looking at pulling the codes and > seeing what the PCM has to say. I never said that it was due to the tune of the engine. I simply disagreed with your crap that engine load has nothing to do with shift points. > > First step would be to check the PCM for codes. Since its a 98, you'll > > need [quoted text clipped - 4 lines] > > Interesting, since thats the first thing I mention doing. And I never said that you were wong there. > >> Correct, but the state of tune would have to be drastically degraded to > > have [quoted text clipped - 8 lines] > It causes a misfire, something that might be a bit more noticable than shift > points. Misfires are not always so easily detected, especially when the PCM will do all it can to correct such things, including things that can have a significant drop in performance but as I say again, I am not saying that this is the cause, only that you are full of sh.t that these things can never happen overnight. > the > > regulator in the fuel pump goes bad > > Poor engine operation would result, but the OP doesn't mention that. Possibly, it depends on how badly it failed. > > or a sensor fails. All of these things > > can happen in an instant. > > Wow, a sensor fails.... what was it that I said to check? LOL, once again you prove your ignorance. Not all failures flash a code since not all failures are complete failures and if the PCM is not aware that the sensor is not functioning properly, no code is generated. > Oh yeah.... > [quoted text clipped - 6 lines] > > Just full of relevant info today, aren't you? No, just like watching you dance when proven wrong.. SignatureIf at first you don't succeed, you're not cut out for skydiving >> >> When a engine is out >> of tune, it will have a higher manifold pressure (lower vacum) at a [quoted text clipped - 4 lines] > tune is irrelevant unless mechanical problems are present in the > valvetrain. You guys are complicating the issue, if the motor is lacking power the accelerator pedal will have to be depressed further to get the expected performance; this will result in the throttle valve cable being extended farther than normal for a given road speed and this results in delayed upshifts. 2 words: proof read. > You guys are complicating the issue, if the motor is lacking power the > accelerator pedal will have to be depressed further to get the expected > performance; this will result in the throttle valve cable being extended > farther than normal for a given road speed and this results in delayed > upshifts. Precisely John, but... the OP doesn't mention any engine problems. What we do have is the OP saying that the shift problem happens at some points but not others. > Hi all,98 Ram 1500,5.9 4x4 Quad Cab.90715 miles. For the past week,it > has started shifting later than it used to,and a couple of times wouldnt > shift out of first unless I let off the gas,then it shifted with up > through the gears. When this happened,I just got off the > freeway,pulling away from a stop sign. It hanging on longer to shift.Any > ideas ,and suggestions would be appreciated. Thanks. The only thing that would have a definite sudden symptom is a sensor. All else would come on gradually. SignatureMax Join www.devilbrad.com and find out what free exchange of info is all about. "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) >>> >> When a engine is out >>> of tune, it will have a higher manifold pressure (lower vacum) at a [quoted text clipped - 10 lines] > farther than normal for a given road speed and this results in delayed > upshifts. >> You guys are complicating the issue, if the motor is lacking power the >> accelerator pedal will have to be depressed further to get the expected [quoted text clipped - 3 lines] > > Precisely John, but... the OP doesn't mention any engine problems. Pardon me for stating the obvious but the OP might have an engine problem and not know it; not all engine problems manifest themselves as misfiring. etc. |
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