[pope]

Originally Posted by vfrqqq

Actually, the machine shop didn't rebalance it after I had it resurfaced, probably since I didn't think to ask. If they only removed 0.030 in of material from the contact surface, would it really be that easy to unintentionally remove more or less in one spot than another? I'm struggling to understand how they could have messed it up so much that I wouldn't have probably seen the error when they were finished, and it looked very uniform when they gave it to me. But I could be wrong.

Ideally, removing an even layer of material would not change the balance. But was the layer removed an even layer? .030” from the highest point might have only been .025” from another point. The whole reason for surfacing is to make a non-uniform surface uniform. Did the material removed have enough variance to create an imbalance

Originally Posted by vfrqqq

As far as the pressure plate being out from the manufacturing process, I understand it's not impossible for it to have been missed, but I also tend to have a hard time seeing how a manufacturer would allow parts that need to be precision balance go out the door without having met their specifications. That would seem to give them a garbage reputation for reliability.

Shit happens all the time in manufacturing. It’s it likely the new clutch and plate were imbalanced, probably not. Is it possible, yes.

Originally Posted by vfrqqq

Regarding the clutch disk alignment tool, I was able to get my transmission back on the engine eventually, but not before I had made some unsuccessful forceful attempts. So if the clutch plate was out of alignment, but I was able to ultimately install the transmission, it sounds like you are saying the transmission essentially got the clutch disk back into position on the input shaft splines, no?

If the disc is on the spines and the transmission is bolted to the engine, it’s aligned. However, depending on what happened during your “forceful attempts” you may have bent or otherwise damaged the clutch disc, pressure plate fingers, throw out bearing, input shaft, etc…

Originally Posted by vfrqqq

I'm concerned about rebalancing the flywheel and pressure plate as I was under the impression the flywheel is balanced together with the crank shaft during the assembly process. As such, wouldn't balancing the flywheel/pressure plate, but not together with the crank shaft potentially put them out of balance?

No. I mean technically yes it’s possible, but as long as the individual parts are balanced within spec, they will remain balanced when assembled. Subaru isn’t perfectly machining individual flywheels for each engine. If that was a necessity, aftermarket flywheels would be nonexistent.
In general, pistons, rods, and crank will be matched to each other to a target spec (although in a boxer configuration matching crank throws to rods/pistons isn’t even a necessity an long as the crank is balanced to itself). Flywheels (etc) will be balanced to the target spec (0oz, 28oz, 50oz, etc. imbalance (can anyone tell i grew up around fords)). Then, if the manufacturer is building engines to a (let’s say) 50oz spec, any 50oz flywheel for that engine model is going to be fine. 0oz (aka neutral balance) engines will use 0oz flywheels, 28oz will use 28oz, etc…

If you’re certain the vibration originated with the clutch replacement, start by dropping the trans and looking for damage. If nothing is obvious, have the flywheel balanced. Then, reinstall and see if the vibration is gone.

Actually, first, unbolt the driveshaft, rotate it 180* relative to the rear-end, re-bolt and torque to spec. I have no idea why this sometimes works, but sometimes this works.