the way you can tell if the bolts have been used to help balance the prop shaft is the length.
We're talking about the six bolts in the CV joints at each end of the prop shaft. If any of the bolts is longer or shorter than the others, that is the clue. If your bolts are not all the same length you MUST put them all back in the same place. EXACTLY the same bolt in EXACTLY the same bolt hole.
When I pulled my prop shaft the first time I marked it with paint but I didn't do a very good job and most of it came off. I don't think the orientation of the prop shaft to the bevel gear or rear diff is really important. I think where it's really important is if you split the prop shaft at the center u-joint - then you really want to be careful to keep the two halves oriented in the same position when you put it all back together. Someone with more driveline experience might correct me on this though - I didn't have any problems with mine though.
I think the front and rear CV joints /are/ actually pretty expensive - currently $289 at FCP. The good news is that they are serviceable and you SHOULD service yours TODAY. Get some CV grease from your local parts place and make sure it's CV grease with Moly and not regular wheel bearing grease. You can pop the top covers off the joint pretty easy and then clean up all the dried up grease inside as best you can, and then pack the new grease in and work it all around the ball bearings. It's not tough, though time consuming and messy. I think I saw a writeup on this on matthewsvolvosite.
I replaced my center carrier bearing and bushing with that from a 7xx. You have to shim the exhaust hanger/bearing mount down away from the car a bit as the 7xx bushing is a bit taller than the one from the AWD cars. Two or three washers is all I am using. Also you'll need a new bearing that fits properly. I used a SKF 6206-2RS1n for mine but I can't guarantee that it will fit for you so you'll have to measure.
The torque steer is annoying but the power increase is plenty nice.
Also FWIW I have removed my prop shaft again for the summer (mpgs, power, also I want to do some work on the center carrier bushing) and found the main bushing for the 'torque tube' is moving and needs to be replaced... probably part of the 'thumping in tight turns' thing...
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1998 V70 AWD->FWD->AWD Turbo 215k+
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