my friend is thinking about buying a 3.8liter v6 auto 87 firebird. the guy said it has some vibration because the torque converter was bolted into the wrong holes, is this possible? sounds like bull**** to me, but i dont know anything about 6 cylinders. my friend said when he fired it up the engine was steady, but for some reason there was vibration in the car, what could cause this?

 

unless teh Canadian models were different, which I doubt, the motor isn't a 3.8, unless it's been swapped. As for teh tq convertor causing a vibration..................well, when we pulled teh tranny off the 3800, & unbolted the tq convertor. I took it home , put in safe place. I was reading the holy book haynes that I got free w/purchase of engine, & it said that if you 're gonna pull the convertor, mark it so that when you put it back, it will be balnced back up. could be the problem right there.

 

unless you went to a lot of extra work there isn't any way to bolt it up in the wrong location. you may be able to install the flex plate backwards and not have the little pads facing out the converter sits aginst when it's bolted to the flex plate. if it mattered where a converter was bolted it's be doweled, reguardless of what a hayes manual says. tell "your friend" to not believe what the guy selliing the car has to say, or have the seller bolt it up in the correct location since it's a fairly simple job.

 

I agree. I asked this of a trans tech when I swapped out my trans, because I wasn't re-installing the original torque convertor. He said the fluid inside the torque convertor will help absorb any vibrations and keep the assembly (flywheel & TC) balanced.

And Psyte, the "basic" way that a v6 operates is the same way that a v8 operates. I say "basic" because I'm excluding differences in computers and fuel injection and etc, but a harmonic balancer, crank, pistons, valves, trans, driveshaft, etc; they all act the same.

 

ive been asking around and alot of people said the vibration is probly due to a slopy drive shaft(eg. worn u joints). is it actualy possible to bolt the flex plate on backwards though? when i was putting my engine back together i actualy did put it on backwards and i couldnt bolt it up because the holes were too far away.

also i have a question on something completely different... i noticed on your uh... thing it says that you have a 700R4 transmission. what exactly do i have on my car then? i could have sworn mine was a 700R4, but if the 6 cylinders have it than its gota be different right? its a stock tranny bolted on to a 5.7L 89 Trans Am GTA, any idea what it is? TH700R4 mabey?