Bump and Shimmy

Alright, maybe someone has some ideas. 1994 Toyota Pickup 4x4 V6 3.0 EFI, 128000 miles. Problem one: After driving, when coming to a COMPLETE stop, there is bump coming from under the car, like something shifted. It may also do this when accelerating from a complete stop. It will never do both, meaning it either does it when I stop or accelerate. It will also not do it if I come to a rolling stop and then accelerate. Thought maybe I should change out the tranny fluid and filter as I just bought this truck a few weeks ago to get me back and forth to work and to haul stuff around and I do not know if the filter and fluid has ever been changed. It definitely seems like it is coming from under the truck where the tranny is. Also, I get a steering wheel shimmy at 40-50mph, doesn't happen at slower or higher speeds. I just had new tires put on and an alignment done. Also there is a bit of play in the wheel and maybe that is related to the shimmy but don't understand why it would do it at 40-50mph and not at 65mph. Any suggestions would be appreciated.

 

Oh, forgot to say that it is an auto tranny. thanks.

 

Sounds like a tranny mount. The shimmy is probably wheel/tire balance--the shop that balanced your tires did a poor job--this is very common.

 

I agree with Redneck

 

Thanks for the replies. How difficult a job are the tranny mounts? Do they need to be replaced or just tightened? Also, I bought the tires at Goodyear and they already re-balanced the tires but said that wasn't the problem - they said I should have the steering looked at but I didn't totally buy that since the problem ONLY seems to occur at 40-50mph. Thanks.

 

You could also have an out of balance driveshaft or one of the weights fell off as well.

Swap the tires front to back to see if the problem gets any better or not. That will rule it out being tire and wheel related.

That being said, you have to change a tranny mount. It's likely ripped.

Check www.autolibrary.org to see if they have the R&R procedure there.

Otherwise, get a hold of a service manual to do the repair.