Hi, I started a thread in the conversion forum but thought this one would be appropriate as well. My other one is here: http://https://ls1tech.com/forums/co...l#post15233206

Basically I have a stock 4L60-E that I think is causing serious vibration in the car. It feels like the motor has solid mounts - I can barely stand to drive the car around.

I unbolted the converter and ran the motor and the vibration went way down, so I suspect it's something tranny related. The engine/tranny combo is from a wrecked '98 Camaro with about 80k miles on it. The tranny has no visible damage and the converter looked really clean, but the pan had a lot of metal in it when I pulled it before putting the drivetrain in the car. I am not sure how much metal is normal for a transmission with that many miles that was likely never serviced. It looked like a thick layer of pencil lead all over the bottom of the pan. The input shaft has no play but the output moves side-to-side far enough to touch the rear seal. I don't know how much play is normal.

I took the car out for a quick drive and the motor runs great, but the tranny doesn't shift very well. Going from park to any gear, the RPMs sort of spike first. Then the 1-2 shift is OK, but the 2-3 shift is really sloppy and worse if I'm giving it more than light throttle. I believe the converter is locking up properly but I only got up to freeway speed one time so I don't have a lot of information to go on.

I know that based on the shifting I'm probably due for a rebuild, but I really just want to know what the likely cause of the vibration is. Bad tranny? Bad converter? Bad flexplate? Something else? Sloppy shifting I can deal with, but the vibration is keeping me from enjoying the car at all. I don't know much about automatic transmissions so I'm at a loss.

Any help you can provide is truly appreciated. Thanks in advance for your time.

Eric

 

Did you check if the converter is bolted in straight? did you check for 1/8th clearance between the pads and the flywheel?

I have some bad news, You may have effed up your pump... good luck

http://www.chevelles.com/forums/arch...p/t-67922.html

 

I didn't check clearances because I figured since everything was stock and came from the same car there wouldn't be any issues.

When I installed the tranny, I put the converter on and pushed it all the way onto the input shaft as far as it would go, jacked up the tranny behind the engine (which was already in the car), put all the bellhousing bolts in, checked to make sure the converter spun freely, torqued the bellhousing bolts, then pulled the converter back out until it contacted the flexplate. I spun it around and put all the converter bolts in loosely, then went back around and torqued them down properly.

I didn't check the gap between the pads and flexplate though. Again, I thought since I didn't change any parts that there wouldn't be an issue. I will check clearances after work tonight.

 

What type of mount are you using "polyurethane" ?

 

The mounts are all rubber.

The motor mounts are these:


The tranny mount is a stock 700R-4 mount, which bolted up to the 4L60-E just fine and fit my crossmember better than a stock mount from a '98 Camaro. It looks like this:


Again, I'm NOT using the tranny mount pictured. Mine's rubber. It's just the same style.

 

I would recommend you do a test.

Put the car on jackstands... basically get the rear tires off the ground safely. Run the drivetrain without the load of the vehicle. Place it in reverse and let it see some rpm, nothing outrageous... just a good rpm so that you can feel it or not.

Do the same thing in all forward gears manually. See if there is a difference anywhere. Also, have someone operate it while you look for any obvious issues with the driveshaft.

Normally the transmissions will not cause an imbalance, but stranger things have happened. You are now at the point where you need to begin ruling things out. Even if they seem trivial. Make sure they are good to go or not.

g

 

^^ poly mount , yes i am ..and do feel some vibration up through the console from time to time..i hear mixed feelings on this, if u want to respond or anyone else, not to hyjack the thread..