91 Q45 driveshaft center bearing replacement

[1bluestraveler]

I've recently had an engine/transmission R&R, within 400 miles the center driveshaft bearing needs replacement. Is there an alinement/shimming adjustment needed between the transmission and driveshaft bearing that the mechanic missed?

[Q45denver]

How do you know it is bad? How many miles on the car? Good idea to replace bad mounts (transmission, engine, driveshaft) to preserve alignment. I have a extra driveshaft with a good center bearing you could have.

[1bluestraveler]

Thanks for the reply, and the offer of the driveshaft. The center bearing was bad, it had a pretty good rumble/vibration at 1700 to 2000 rpm. My understanding is that during '91 they came out with a beefier center bearing. So I found an upgrade at a yard for $50. I put a JDM engine and transmission in, so I have a complete engine and transmission sitting around for parts. So keep that in mind if you need something.

[Q45denver]

Not sure about the improvement in 1991 but there was an improvement in 1994 to the insulation which was breaking done in the earlier ones and causing balance problems. I put a new one in mine and noticed a slight improvement. I have a couple of parts engines with rod knocks as well. What was wrong with yours?

[JedCoop]

Good idea to replace bad mounts (transmission, engine, driveshaft) to preserve alignment. I have a extra driveshaft with a good center bearing you could have.

I am in the process of changing out mounts on my '92 and was waiting before doing the driveshaft. But if a good drivehshaft is available, I am interested (assuming 1bluestraveller isn't). Did the car this came out of have TCS? I know that the part numbers for driveshafts from TCS and non-TCS cars are different, but I don't know what the actual difference is.

[1bluestraveler]

That's what I understand Jedcoop, the traction control cars are different. At a local yard I found 2-93s and 1-94 Q's being parted out, none of them were traction control tho. I found several others around Denver, already out of the car for $100-150. You probably have a pretty good quantity in your area as well if (Q45denver's) doesn't work for you. My parts engine was rebuilt by someone who had high confidence/low competence, it's not been torn down but brass was found in the pan so it's probably a spun bearing. Approx. 150k miles, different crank, also changed 1 head. The transmission is 150k, running great when it was pulled.