740 pinion seal replacement

Hi,
I have a pinion seal that is allowing lubricant past it.
I do my repairs in the driveway and am looking for pointers
to taking this on myself. Are there any special tools or
fixtures needed to do this? I have never had the axle apart on
this or any other car and don't want to create problems. I have
limited experience, I know the only way to get experience is to do
the work. Model year is 1990 and mileage is around 175K to 180K

What is a common mileage range for the pinion bushing to
need to be replaced? If I am doing the seal I would not want to
over look the bushing (or is it called a bearing?).

Thanks for any suggestions.

 

The job consists of disconnecting the driveshaft, removing the big nut
in the center of the flange, pulling the flange off, prying out the old
seal, then the reverse to reassemble.

The only problem is getting the flange off, sometimes. The big nut
inside the flange can be quite tight, if you don't have access to an
impact gun, you'll need to have a friend hold the wheels still with the
brakes unless your parking brake is really good. Remember: If you're
up on ramps, trying to turn that nut will move the car!
The old seal will pry out quite easily.

There's no need to do anything else - in fact if there's any problem
with any of the bearings you'd know about it already - you'd be
complaining about the noise. Only the auto trans has a problem with the
rear bushing wearing that usually needs to be changed the same time as
the seal.

--
Mike F.
Thornhill (near Toronto), Ont.

Replace tt with t (twice!) and remove parentheses to email me directly.
(But I check the newsgroup more often than this email address.)

 

Thank you Mike!
I am concerened about being able to come up with enough torque while under
the
car, just not a lot of room. I am glad you pointed out that the car will
move if on ramps.
I have 2 jack stands that I will place under the rear axel, then I will have
to depend on
a friend and the brakes to get the big nut off and back on.
I have on my list of things to get is impact gun and a
BIG compressor to run the thing, but that is in the future. Do you happen to
recall
the correct socket size for this large nut? I would like to attempt this in
one try
so knowing I have the correct size socket would be very helpful.

I plan to buy an impact socket if it is a size I don't own, Would regular
depth work?

I have found an artice on a webpage that talked about the parts needing to
marked
and oriented to prevent excessive vibration (balanced at the factory in a
particular
orientation) and how to refill the case with a long hose.

Would you mind commenting on the orientation thing and any other tips that
you
can think of would surely be helpful?

Last thing I guess I need to know is the torque setting that I need to get
this set back to?
I think my torque wrench only goes up to 200 ft lbs.
Really appreciate the help in keeping my Roller going.

 

http://www.brickboard.com/FAQ/700-900/Driveline.htm
They don't talk about the socket you need, and it's been quite a while
since I've done this, but as I remember a normal depth socket is all you
need, and as for size, I think 24mm, but it may have been 22 or 27.

When in doubt, mark everything with scratches so you can put it back
together exactly as it comes apart.

--
Mike F.
Thornhill (near Toronto), Ont.

Replace tt with t (twice!) and remove parentheses to email me directly.
(But I check the newsgroup more often than this email address.)