AussieNath

Yes, the parts required to replace an intact diff include....

1. Q2 diff
2. 2 tapered bearing sets
3. driveshaft seals (they are different on left and right and the right side is double the cost of the left).
4. loctite 510 or similar (no gaskets required)
5. new gearbox/diff oil.

I would encourage anyone with decent mechanical experience to have a crack themselves. You will need a decent amount of tools to do the job. I found my adjustable head ratcheting spanners a godsend for some of the difficult to access bolts. I would also recommend a large and good quality set of car ramps plus car stands. Access to a hoist would be superb.

The job takes a day to do if you know what you are doing, obviously a lot longer if you don't. I found the CD workshop manual was practically useless.

When looking at preload, you can set it back to the original factory spec. With preload, what you are trying to avoid is lateral movement of the diff.....this causing a clunking/banging noise every time you go on and off the accelerator. It can also damage the bearings over time. It is also important make sure the preload is noe too high otherwise you put too much pressure on the bearings and they will be damaged after only a few thousand k's/miles.

In regard to the feasability on a JTS, I wouldn't bother. I've not personally known of anyone with a JTS to blow a diff. If money was no object and you wanted LSD, then sure.....but if money was no object, you would probably own a Zonda or something