Heatmaker

Hello all....

Lately I"ve been having problems with my car. I've been feeling heavy vibrations in the rear of the car when I go over 70 or so.... really I should say it's a low vibration and barely noticable when under 70... but as soon as you start goign past 70 the car vibrates like a ****... And it seems to be drivetrain related... but I have no idea what could cause this... I have 4:10's with the Aluminum driveshaft... and it almost reminds me of that "vibshaft" shaft feeling ... only not as aggressive.. any clues as on what I should check out? BTW I have an inland Empire driveshaft...

94zrag

If it's only happening at certain speeds, than most likely it's just that your tires need to be balanced.

pHEnomIC

I would say that the tired need to be balanced and you may need to check your driveshaft. I heard some stuff about our cars shaking at high speeds because the driveshaft is weighted or something on one side and it creats a lot of centrifigul force.

Heatmaker

Yeah..... I thought that too... and I had my Tires balanced today.... No Dice...

But would an alluminum drivesahft be able to all of a sudden become unbalanced?

Spinner

If it had stick on weights, there you go. Could also be old saggy mounts/bad pinion angle.

Heatmaker

I have stick on and knock on weights... but it's not the tires....

It's something else.... I have the LCA relocation brackets... and the other goodies.... so I doubt it's the pinion angle... But what do you mean by bad mounts?

Heatmaker

ANy other idears folks? ... thanks for al lthe replies...

snorkelface

Has the virbration been present ever since the driveshaft was installed? Is so, try flipping it over and re-installing.

Kurt Crosbie

I am having the same exact problem!

I just got my motor changed out and it started happening after the swap (I got the rear gears changed too)

Is it hard to take the drive shaft out? Where would I go to get it balanced?

Transplanted LT

OK, guys, here's my take. Alignment, tire balance, driveshaft, tail shaft housing bushing. If it's not alignment or tire balance then it might be driveshaft (if it's aluminum it probably isn't that - unless you drove over something and it got hit from underneath). Before you pull the driveshaft and take it in for balancing - grab the drive shaft yoke at the tranny and wiggle it fiercely. If there is ANY "noticeable" play, it is probably your bushing in the tail shaft housing that needs to be replaced. Not an uncommon problem in 4L60Es.

If you've got play, remove the drive shaft, drop the crossmember, pull the trannsy tail shaft housing and take it in to your local tranny shop. Have them replace the bushing and seal. Probably $10 or so. Reinstall. If you've still got a vibe then I don't know what to tell you, other than some tires are not truly "round" and can cause vibes at specific speeds......gets worse as you go faster.

Heatmaker

I have a manual T-56

med_reject

tread wear can do that too. My car shook badly after 85mph until i changed the tires.

ShawnMacAnanny

Maybe you or an idiot previous owner used fix-a-flat That stuff will cause it to vibrate really bad.