Derf00

When did the problem start and have you recently modded anything before it started....?

jaygt88

I just picked up the car and looking today I have a tremic and a stock ds out of god knows what and I'm not sure its the correct size and the piniin angle seemes to me fine used an angle finder and matched up I think that the ds may ne my issue I'm bringubg it to a mustang performance shop soon to see what he thinks. The last owner told me today he had a ford aluminum ds in it and sold it and threw a ds that je had sitting around in it

jaygt88

Ok so I bring the car to a mustang shop and the guy takes my driveshaft out finds that my yoke is gone and pits on another used stock ds takes it for a ride and tells me its better but not great and tries to tell my my rear end is blown out and wont even take me for a ride or let me try it with his used ds. Now mind you he is telling me he will rebuild it for a grand on top of selling me a new ds. And when I got the car it jad a recent rear end rebuild with 4.10s from this same shop I have the paperwork for this lol. Anyway looks loke I'm goint to het a fr aluminum ds and also take the diff cover off and insprect it myself just to be sure because this guy never did

65Raven65

The first thing I thought of when I read this was - driveshaft.

Try an aluminum one from Ford.

I had a really bad vibration in my old '89, and the aluminum DS fixed it.

Good luck.

jaygt88

Saving up my pennies and then we will see if the ds helps

jaygt88

Ford aluminum driveshaft ordered will be in on monday ill keep posted

wydopnthrtl

When I put in 4:10s I had the same issue. New aluminum one and its much better.

You could also have a worn tranny tailshaft bushing. On a different mustang I've had that cause a vibration at coasting and just keeping speed.

jaygt88

Ya I figure I'm going to repkace the taulshaft bushing at the same time and I also have 4:10s hope this works and ide be upset about all the snow we have on the way but hey it will keep me frim driving nefore I repair the car

jaygt88

New drive shaft in and problem fixed no vibration at all took it up to 90 and drives like a dream

DocSnickers

Just as a thought, have you looked at the lugs? Depending on the style of wheels on the car it could have oval washers as opposed to circle washers. Which if you have circle washers on wheels that should have oval washers its going to vibrate.