Shad Laws

Hello-

My left-side axle seal in the differential is weeping. Time to replace it! I've read up in the service manual, but have two questions:

1. How high is the oil level relative to the seal? Do I really need to drain the fluid to do the replacement? It'd sure be convenient if I didn't have to...

2. Should I just replace one, or is the other one probably about dead and should be replaced, too?

Thanks!

Take care,
Shad

BigIslandSevens

iTrader: (4)

When was the last time the fluid was changed? If it has been a while i recomend just dumping it and filling with new oil. As well i would change both seals at the same time. Because Mr. Murphy will show his face the second you drive away. And the other side will start leaking.And new oil will just reasure you the diff is happy.

However. When doing this job, be prepared to replace the wheel bearings in teh rear spindle/hub. The axles are sometimes siezed in there very badly. There is a thread by DamonB about the bearing job. Not the most fun thing in the world to do.

When you have to go in that deep,on an old car(10+ years) expect the worst and be prepared with the parts. Just my advice from my experiences with every axle removal i have ever done on these cars.

DamonB

If he's just replacing the oil seals on the diff that won't be necessary. All you have to do is remove the top and bottom bolts on the upright along with the outer bolt on the toe link and you can pull the axle from the diff without even having to remove the axle nut or disassemble anything else.

I would carefully remove the metal bands around the rubber boots on the inner axles and then remove the rear brake caliper. Remove the two bolts in the upright (hub carrier) along with one of the toe link bolts. You can then carefully pull the axle out of the drive cup in the diff, boot, grease and all. Put a plastic bag over the axle so you don't contaminate the grease with dirt. Now all you have to do is grab a prybar and carefully pry the drive cups out of the diff and then you can remove and replace the oil seals.

If one is weeping I would go ahead and do both.

BigIslandSevens

iTrader: (4)

^^ I thought of that last night while sleeping, That you can just swing the whole assembly up and out to give you the clearence. thanks for the catch
I would still recommend checking the condition of the wheel bearings while you are in that area anyways.

I could of sworn that the axle will clear the diff with the inner cup still attached

DamonB

I can't say for certain, it might. I err'd on the side of caution.

The only time I pulled the axle from the drive cup I removed the entire upright since I needed the axle/hub off the car. Maybe removing the lower bolt on the hub at the lower lateral link will let the hub pivot away enough to pull the axle from the cup. Worth a try.

Shad Laws

Thanks for the replies, guys!

I replaced the diff oil about 6 months ago with Redline, so it doesn't *need* to be replaced. Plus, I don't happen to have a hand pump here, so it'd be kind of a pain. Is the level low enough to where I don't have to?

Sounds like replacing both seals is a good idea. Re: wheel bearings, I was thinking about that, too. I've already replaced the fronts (I drive very aggressively... after 45 minutes of hard driving, when things are quite hot, I'd launch into a hard corner and the front wheel bearing of the outer wheel would start ticking!). I should check into the price of the rears.

I hadn't thought of the idea of removing the whole knuckle to avoid dealing with axle nuts - it's a good idea :-). If I decide to skip the wheel bearings, I may very well do that.

Thanks!

Take care,
Shad

BigIslandSevens

iTrader: (4)

Hey shad,

as far as the oil level goes, I think it will be OK not to drain it. I can't remember for sure if the seals lower edge is lower than the filler plug. Since that is what you let drain to the proper level just look at it while you are underthe car. If the seal is higher up than the filler, than you should be ok. You may end up just losing a little fluid instead of the whole deal. Just make sure if you are doing this in a garage(without a lift) that you jack the front of the car up to level with the rear.

A trick i use for filling diffs without a pump is to get a long length(10 feet or so) of clear nylon hose. ( Small enough to fit in the filler whole and for the oil bottle tip to fit in)

Then lower the car to level and raise the hose higher than the diff. You cansquish the bottle to help the flow along. When it overflows out the filler hole, remove the hose and let it drain to level. A little crude but it works with the small area they gave us to work.

And swinging the whole spindle up is what i remember doing to get the axle out when i had to drop my diff housing. The retail price for the rear bearings is around 90 bucks each side.(i think) I know that Ray @ malloy or mazdacomp should be able to beat that. But they are huge pricey bastards.

Dave

Shad Laws

Hey Dave-

I've used the same long hose trick before myself :-). The only difference is that my version includes two additional tools: a pair of "needle-nose style" vice grips and another person. One person is pouring in the oil from above. The other is making sure it goes in the filler hole. Then, as soon as it's full, they use the vise grips to clamp off the line so we don't have to clean up the giant mess caused by all the oil in the tube dripping onto the floor. Having worked on so many old Porsches and VWs, I've come to hate oil messes... :-).

I called Ray at Malloy today and he said they were about $60 ea. It's not a bad price, but it's also money spent on something that doesn't need replacing yet and is just as easy to get at on another day :-). Still cheaper than the fronts... they were somewhere around $100 or more if I remember correctly.

Thanks!

Take care,
Shad

afterburn27

iTrader: (5)

I know... an old thread.... but I just replaced my diff side seals today.

You do not have to drain the diff fluid to change the seals because they are located above the fill plug. I went ahead and put in some royal purple 75w-90 (love that stuff).

Like BigIslandSevens mentioned, the axle will clear the diff with plenty of room with the drive cup still attached, I didn't take the boots off or anything.

1. remove wheel
2. remove abs sensor
3. remove brake caliper
4. unbolt toe link
5. unbolt upper and lower 'hub carriers'
6. hold hub assembly while prying the drive cup out of the differential (it will pop out with some force)
7. pry old seal out
8. tap new seal in (make sure to apply some new diff oil around the edges of the seal)
9. Line the axle up and push it into the diff with the retaining clip opening facing up
10. You will probably need to use some force to push the axle into place, I used a large socket and tapped from the other end of the axle until it popped in.
11. Replace upright bolts, toe link bolts, caliper, abs sensor and wheel.
12. Drink cold refreshment!