(Solved) Rear end chatter...

shooter902 · Aug 11, 2010

hey gang,

About 3 weeks ago I just changed out my rear end dope after 70,000 with a couple of bottles of Royal Purple 75W90. Looked at everything and didn't see anything suspicious. Last week I put a Transgo kit in the tranny and all went well, but when I had the car up on jacks to run it through the shifts to see if everything was shifting properly when it hits 3rd gear I get this awful chatter from the rear end. I put a stethoscope on everything and it sure sounds like its coming from the rear end, unless its a U-joint locked up and making noise and traveling?

My Question is: Is it normal to have chatter when there is no load on it like that? I was hitting 50 or 60 with the wheels off the ground. I don't hear anything noticeable while I am driving it except a disappointing squeak (Control arm bushings??) instead of a tire chirp 1st to 2nd, But I am working on that one :laughing5: Any ideas? Man I hope its not the gears..AGH!

Thanks

JDwhite98gt · Aug 11, 2010

Re: Rear end chatter...

Um you are definitely not supposed to run the car with it off the ground, run the car on the street and I bet you dont have that chatter. Hopefully you didnt do any damage

shooter902 · Aug 11, 2010

Re: Rear end chatter...

Well, that's what I was thinking too, I mean I have done it when I was wrenching, but the Transgo kit said to run it through its gears while it was off the ground so that's what I did? I guess I could pull the cover off again and see if I can see anything!

JDwhite98gt · Aug 11, 2010

Re: Rear end chatter...

Does it make the noises while driving around the streets?

Gregor185 · Aug 11, 2010

Re: Rear end chatter...

running them in the air wont hurt anything...did you put the friction modifier in the rear when you did it?

JDwhite98gt · Aug 11, 2010

Re: Rear end chatter...

Well ive been told that having the var off the ground lets everything hang therefore putting stress on the drivtrain, distorting the pinion angle from where it would be if it was on the ground. That coulod be false but it makes sense to me. If it is completely false then I retract my current statements

massacre · Aug 11, 2010

Re: Rear end chatter...

I'm sure Trans go told you to run it through the gears, but I doubt they said to do it @ 60 MPH.
Usually you run the car through the gears to get all of the fluid distributed throughout the valve body when re-filling the transmission.

shooter902 · Aug 11, 2010

Re: Rear end chatter...

Wrong you are Massacre! They wanted me to take it up to 55 with OD off. they show it in their video as well...but thanks for the input, it kinda scared me to do it!

IT does seem to make sense to me too JD, but that is what they told me to do??

Gregor185..you get the points!!!! I looked into to further and figured out that it might be the clutch packs making noise and NO I didn't put the Modifier in like a dumb A$$ I didn't I needed to? So right after I posted it hit me and I ran up to the dealer and grabbed some, dumped it in and bingo! Quieted it right down!

Many thanks to everyone for the input..this forum rocks!

Ciao

massacre · Aug 12, 2010

shooter902 said:
Wrong you are Massacre! They wanted me to take it up to 55 with OD off. they show it in their video as well...but thanks for the input, it kinda scared me to do it!

^^^ well then this explains why I will never put anything from TransGo in my car.