Home | Contact Us | FAQ | Search & Site Map | Link to Us
Sign In | Join | Other 45 Sites in Network
HomeAnnouncements
Discussion Groups
By Brand
BMWChevroletDodgeFordGMHondaLexusMercedes-BenzNissanPeugeotToyotaVolkswagenOther Brands
By Topic
4x4 CarsRVsDrivingMaintenance & RepairCar AudioCollectible Cars
Country Specific
Australian ForumsUK Forums
ArticlesAuto InsuranceBuyingCars & TechnologyMaintenanceMiscellaneousSafety
DMV Resources
Related Topics
MotorcyclesBoatsMore Topics ...

Car Forum / Ford / Ford Mustang / October 2004

Tip: Looking for answers? Try searching our database.

Bad vibrations in my Fastback 65 - Ford 9 inch rear end

Thread view: 
Enable EMail Alerts  Start New Thread
Thread rating: 
Mr Nospam - 24 Oct 2004 17:14 GMT
Hi!

I have a problem with vibrations in my Mustang
Fastback 65 with manual transmission and Ford 9 inch
rear end.

At 55-60 mph, it starts as a vibrational sound but almost
no vibrations are felt in the car.
Above 65 mph, it get's worse and it's a loud sound in the
rear and lots of vibrations.

Motor mounts new, u-joints new, no play anywhere
in the driveshaft, new rear tires and also balanced,
no play in the pinion bearing, some play in the rear
end of the transmission but the vibration sound is
further back.

The car has been like this since I bought it and I've
switched several parts but the problem doesn't go away.

I need some help with this.

Thanks,
Sverker
Dinsdale - 24 Oct 2004 17:54 GMT
>Hi!
>
[quoted text clipped - 20 lines]
>Thanks,
>Sverker
Well I take a shotgun guess.

Check the driveshaft balance.
Might try repositioning the driveshaft on the differential (but with
all the checking and replacing you've probably done this already)

Does it have drums?  Can those go out of balance? Mine have what look
like weights attached.  Some shops can balance wheels on the car
taking consideration of all the rotating mass.

How about the condition of the axle bearings.

Worn shocks, leaf springs, and/or bushings could magnify an imbalance.
Mr Nospam - 24 Oct 2004 23:18 GMT
Dinsdale <back@ya.com> wrote in message
> Check the driveshaft balance.

That is one of the things I plan to do.

> Might try repositioning the driveshaft on the differential (but with
> all the checking and replacing you've probably done this already)

Yep, doesn't help.

> Does it have drums?  Can those go out of balance? Mine have what look
> like weights attached.  Some shops can balance wheels on the car
> taking consideration of all the rotating mass.

Yes it's drum breakes, you're right the drums should be
balanced as well!

> How about the condition of the axle bearings.

new..

> Worn shocks, leaf springs, and/or bushings could magnify an imbalance.

quite new.

One thing I forgot to say clearly about the play in the rear
part of the gearbox.. There's some play in the mounts, not in
the gearbox itself. Could that be something?

Thx!

Sverker
Jim Warman - 24 Oct 2004 18:30 GMT
Is the vibration constant or does it change as you move from accelerate to
float to decellerate? How about a neutral coast down (move the shifter to
neutral and allow the car to slow on it's own)?

> Hi!
>
[quoted text clipped - 20 lines]
> Thanks,
> Sverker
Mr Nospam - 24 Oct 2004 23:23 GMT
There is not much of a difference whether I accelerate or
decellerate.

In neutral or with cludge down, the vibrations seems to
increase slightly.

Thx!

Sverker

> Is the vibration constant or does it change as you move from accelerate to
> float to decellerate? How about a neutral coast down (move the shifter to
> neutral and allow the car to slow on it's own)?
David M - 24 Oct 2004 23:56 GMT
> In neutral or with cludge down, the vibrations seems to increase slightly.

What's a cludge?   Maybe you meant "clutch".
Mr Nospam - 25 Oct 2004 20:16 GMT
Yes that's what I meant.

/Sverker (swedish mother tongue)

"David M" <NOSPAM@nospam.com> wrote in message

> What's a cludge?   Maybe you meant "clutch".
Wound Up - 25 Oct 2004 20:22 GMT
I once heard an Australian or New Zealander guy call it the "collywobbles".

> Yes that's what I meant.
>
[quoted text clipped - 3 lines]
>
>>What's a cludge?   Maybe you meant "clutch".
Backyard Mechanic - 24 Oct 2004 19:49 GMT
Mr Nospam opined
> I have a problem with vibrations in my Mustang
> Fastback 65 with manual transmission and Ford 9 inch
[quoted text clipped - 4 lines]
> Above 65 mph, it get's worse and it's a loud sound in the
> rear and lots of vibrations.
........
> The car has been like this since I bought it and I've
> switched several parts but the problem doesn't go away.

Clue is "the 9 inch"

Maybe it was installed wrong.

It's imperative that, at rest - normal ride height- the pinion shaft and
trans tailshaft be aligned at the same angle with respect to grade...that is
the pinion shaft should NOT point directly at the tailshaft, note the
tailshaft doesnt point at it.

An imaginary line extended from the center of each shaft should be equal
distance apart at both ends.

Also if the driveshaft was "built" make sure the u-joint ears are aligned
properly with regard to each other, IIRC.. it's 90deg, not zero
Mr Nospam - 24 Oct 2004 23:45 GMT
Backyard Mechanic <pettyfog@Yaywho.com> wrote in message

> Clue is "the 9 inch"
>
[quoted text clipped - 6 lines]
> An imaginary line extended from the center of each shaft should be equal
> distance apart at both ends.

The Ford 9 inch was probably not on the car back in 1965, since
I read that only those with the high power engine had it.
So someone put it in and it's hard for me to tell if they did
it right. Looks like fine job, though I haven't looked
at those angles you mention. How much would be appropriate?

> Also if the driveshaft was "built" make sure the u-joint ears are aligned
> properly with regard to each other, IIRC.. it's 90deg, not zero

The front u-joint is symmetric. The rear one is not but can
only fit one way. 1 1/8" cap for the rear end and the
smaller 1 1/16" at the drive shaft. The overall width is 3 7/32"

Thx!

Sverker
Backyard Mechanic - 25 Oct 2004 03:32 GMT
> Backyard Mechanic <pettyfog@Yaywho.com> wrote in message
>>
[quoted text clipped - 8 lines]
>> An imaginary line extended from the center of each shaft should be
>> equal distance apart at both ends.

Looks like fine job, though I haven't looked
> at those angles you mention. How much would be appropriate?

I dont think you understood...read what I wrote about that... it is NOT a
stated angle... it refers to two planes.  Clarified:
"...imaginary lineS  extended from the center of each shaft should be
equal distance apart along their lengths"  

Look here..
http://www.drivetrain.com/driveline_angle_problem.html

> The front u-joint is symmetric. The rear one is not but can
> only fit one way.

Not what I meant but I was wrong... it's zero... (just did a search)... that
is let's say you were to remove both u-joints from the driveshaft on each end
the ears would remain.  The ears should be at the same side of the driveshaft
as you sight along it.  not 90 deg or at a random angle ...
B2723m - 29 Oct 2004 00:19 GMT
First things first...get the transmission mount repaired/replaced.  If the
tailshaft is moving side to side it's intoducing another angle that the
U-joints have to contend with and aren't designed for.

bradtx
 
Sign In
Join
My Latest Posts
My Monitored Threads
My Blog
My Photo Gallery
My Profile
My Homepage

Start New Thread
Enable EMail Alerts
Rate this Thread



©2008 Advenet LLC   Privacy Policy - Terms of Use
This website includes both content owned or controlled by Advenet as well as content owned or controlled by third parties.