So I drove the T/A over 900 miles on a trip recently and noticed that there was significant vibration. Not at all speeds but especially noticable above 60MPH. Initially I thought it was the driveshaft I put in but when I took the car out of gear at speed the vibration went away as the engine revs droped. This made me think "aww S*&T", the motor is imbalanced or losing compression somwhere.

So I did a little reading on here and did my compression check, All 185-190 (whew! ). I also read that a couple members had a torque converter out of balance and unbolted it to test the engine alone.

Voila, the vibration went away with the converter unbolted. Motor reved great too (gotta get me a standard V8 one of these days).

So the question is -- is my diagnosis correct? Is the torque converter out of balance? It is a 2200 RPM "S10" converter I got from GM parts direct. Cheap I know but I thought it would work since Ive heard lots of guys getting one.

Next question would be, How the heck should I balance it. I really dont want to drop the trans so I wonder if I could put some weights or washers on the bolts to test it then weld on some weight when I get it right.

Thanks for any help.

 

trial and error between the convert and flywheel. spin the converter and rebolt it just dont use those same way that you had it bolted before

 

You mean Reclock it compared to the flexplate? I thought the flexplate and converter was supposed to be neutrally balanced...

Hmm ok.

 

Try what balck suggested.

"supposed to be" and "is" are often 2 different things.

It's worth a try; if the 2 things happen to both be unbalanced, and you have their "unbalance" lined up and adding together, you might be able to un-align them and make it ALOT better, with about 10 minutes of work if you're slow like me; FOR FREE. Free is good.

What have you got to lose by trying it?

 

well I did it once and no dice. still a good vibration at 2000. I can try the last position but it takes more than 10 minutes (not to bitch). You must be fast since I have to get up and lay down like 6 times to unbolt then turn the engine for each bolt. takes me like an hour and I am slow so dont rub it in!

 

There's a great tool you can get to turn the engine by the flywheel teeth that makes it go a lot easier.

 

boy I wish I had one of those!

 

Did the problem occur after you installed the converter? Any other changes? How many miles on the trans?

 

This was the first long trip where I was able to notice and not be concentrating on something else. I guess its always been there since I installed the converter about 2000 miles ago (but 2 years). At that time I replaced the converter, Flexplate, balancer and driveshaft. The trans hasnt ever been opened since I bought the car 9 years ago and has around 140K on it. But it seems to be shifting well and no leaks.

If this last clocking does not fix it I think I will take one of the stickon weights I have and put it on the converter behind a bolt opposite the external weight on the flexplate.

 

Ok, this time it did make a little difference. The vibration wasn't so "notchy" in that it is kind of less that it used to be but all over the RPM range. I guess that will do me ok till I can spend more time on it.