I have a 98 xk8 conv. Recently, the trans. died. 101,000 miles. I found a used unit with 58,000 miles. My shop put it in. Around 40, the car starts vibrating. At some point, the steering wheel shakes. I believe I've eliminated brakes and wheels as a source. The trans seems to run well, it doesn't make sense it would be that. Does the driveshaft have to balanced to the replacement trans? Sounds dumb, but I'm grasping at straws here.
thanx
Don

 

Don, I'm stumped. Its speed dependent not rpm dependent right? Happened right after tranny swap right?
From my experience an unbalanced drive shaft vibrates well before 40mph, but admittedly that's experience with a 1986 Ford Bronco II.

If, by chance someone does not jump in, a proper wheel balance is cheap enough to try. Now that would be speed dependent.
Did you replace the transmission mounts? Smarter folks - will this cause vibration? Is it mandatory at 100k miles?

Don please confirm that no other work was recently done.

I too have a 98. My tranny went 18 months ago. I'll be following this one!

John

 

There is a rubber doughnut in the driveline ,not sure if they touch that but I did have a car with one where they missed off a washer from one of the six bolts and it vibrated like hell. If it was the drive line it would vibrate the whole car .
Balance weight on a wheel got knocked off ??

 

I limped the car into the shop, and it was totally smooth, although slipping like crazy. Somebody would have had to knock off a wheel weight in the shop. Mechanic thinks it's grabbing brakes. I jacked car up all around and wheels turn pretty free. This is a two piece shaft, no? Maybe they weren't reassembled right. Or, John, maybe something as stupid as a missing washer. I'm going to have someone else have a look at it.

 

Slipping?

 

hi all;
driveshaft fixed. took to trans specialist. the shaft had a large dent in side large enough to send off its axis. no idea how it got there. when trans was changed, shaft was left on car laying on the braces. replaced with used unit no vibration.

 

Nice!
I'm taking notes!
Thanks for the lesson 😊