How to remove final drive unit (?)

[redrover]

Gents,

MOT's up at the end of March and I'm fairly willing to bet the brakes won't make it through. So in a gap in the weather over the next few weeks, I'm getting my hands dirty and redoing the lot.

I haven't got access to a pit or ramp, but I've got myself a set of 3 ton axle stands, a matching trolley jack, lengths of 4" industrial angle iron (ex-GPO Strowger main frame if anyone used to be a Telecoms engineer), and some lengths of hardwood 4x4 to prop everything up.

I've been looking at Quattro's sticky post on the rear caliper overhaul, which is going to be a massive help, but does anyone have any pics/advice on what is the easiest, safest and most practical (if all three are possible!!) method of getting the diff down on the deck to work on? I'm concerned as much about getting it back in position as removing it.

I'm going to be rebuilding the calipers, fitting new pads and discs, goodridge hoses, changing the diff oil and mounting bushes, greasing the prop shafts and checking the UJ's for any signs of wear (only 45k miles so should be passable). Is there anything else I should be looking out for/changing while I'm there? As I'm sure everybody will appreciate, I really don't want to be doing this job again any time soon!!

Cheers all.

 

[harveyp6]

I wouldn't remove the diff to do any of the things you list, I'd do it all in situ.

If you do drop the diff out then lower it on a jack while the pinion is still resting over the pinion crossmember, but beware that the diff is off centre so tends to roll off the jack.

 

[chrisyork]

I agree with Harvey ! I doubt though, if you will detect any problems with the UJ's in situ. They ought to be changed on age alone, and you often find that once removed they are in quite bad condition even with no play eveident in situ. Mileage isn't the only issue! Also while you are up there it would be a good idea to check the rear diff mounting bushes. Easy to change, and make a big difference to driveline snatch if there is anything wrong with them. The nearside always goes first.

Chris

 

[harveyp6]

I doubt though, if you will detect any problems with the UJ's in situ. They ought to be changed on age alone, and you often find that once removed they are in quite bad condition even with no play eveident in situ. Chris

You will detect play in the driveshaft u/j's if you disconnect them at the disc end (as i always do when doing calipers and/or pads) because that enables you to move them through their full range of movement in the same way as if they were totally removed. With them connected at both ends you certainly won't though.

There isn't any job that I can think of offhand that I would remove the complete diff unit for, other than to thoroughly clean and paint it.

 

[redrover]

Cheers for the quick replies, guys.

If I'm leaving the diff in, can I still easily remove the calipers to work on them off the car? I'd just like to make things as easy as possible for myself!
How difficult will realigning them be?

Chris, I am planning to change the the diff bushes as it happens- there is quite an audible soft clunk from the rear when moving away in first or reverse- even at low revs, which probably means they've rotten away! I'll probably do the UJ's as well if you recommend it, false economy not to I suppose!

Thanks for the advice- a bit of a load off my mind (and an even bigger one off my trolley jack!!) to be able to leave the diff in situ. Only thought about dropping it to the deck as another owner I spoken to said he's done a few that way, and Quattro's caliper overhaul was done with the whole diff away from the car.

Thanks!

 

[Demetris]

there is quite an audible soft clunk from the rear when moving away in first or reverse- even at low revs, which probably means they've rotten away!

It ain't necesserily so!
Mine did exactly this and it turned out to be something from inside the diff.
I took the chance and replaced it with a 3500 unit. You'd better drive the car over a pit or on a lift and with the handbrake on try to replicate the clunk while someone who knows what he's looking at checks underneath.
Just 2 words of caution. Exhaust fumes being heavier than air tend to fill up the pits, so have this in mind for the person that will be underneath. Be really gently with the clutch you don't need to release it fully to check for the clunk.

Otherwise, the rear brakes are quite accessible with the discs out of the way.