1987 fluid all over passenger rear brake & wheel.

[luftwaffle]

Hey guys, I noticed the other day my rear passenger wheel had a puddle of fluid on it, and today the whole rear brake was covered in fluid. I assume it is brake fluid, what would cause this? Thanks.

 

[adsm08]

Pull the drum off and take a look. It is one of three things:

1) Blown/leaking line

2) Blown/leaking wheel cylinder

3) Axle seal


First thing is to ID the fluid. Get some of it on you fingers and rub them together. Brake fluid will get sticky, gear lube will stay slick.

 

[cvar]

One of 2 things: your wheel cylinder (inside) is leaking, or your brake line (outside) is leaking. Commonly it's the WC, which is inexpensive (abt $15), since it's the moving part and its rubber seals don't last forever.

 

[adsm08]

Actually, I have seen the axle seal do that too. He said he thinks it is brake fluid, but he isn't sure. Once he is sure it is brake fluid then it is one of two things.

 

[luftwaffle]

Thanks for the speedy replies guys. I got some on my finger and it stayed slick, so I guess it is the axle seal.

 

[Tedybear]

Thanks for the speedy replies guys. I got some on my finger and it stayed slick, so I guess it is the axle seal.

Slick is a good sign of that gear oil. The other is the god awful STINK of sulfer...

S-

 

[luftwaffle]

Damn, was hoping it would be something easier to replace.

 

[adsm08]

Axle seals aren't that bad. Just time consuming.

Do yourself a favor. Do both of them at the same time.

 

[kimcrwbr1]

Since you have to drain the gearbox you may as well replace both wheel seals and give the carrier a good eyeball and check the gear lash between the ring and pinion. It could be a wheel bearing going bad also. If in doubt now would be the time to replace them as well.

 

[cvar]

How often should we be changing those seals? Mine are still factory originals. Is that bad?

 

[kimcrwbr1]

When they start leaking, normally there is a reason why the wheel seals go bad usually a wheel bearing allowing the axle to flop around.

 

[jhammel85]

Yep, only need to replace as they leak. I did mine a few years ago and it's not that bad of a job at all. Just take your time.

 

[luftwaffle]

Might be a stupid question, but what part do I need to order? axle shaft seal or ?? and for the rear wheel bearings, not sure if I have 8.8 ring or 7.5 ring rear.. Thanks

 

[zekew64]

Might be a stupid question, but what part do I need to order? axle shaft seal or ?? and for the rear wheel bearings, not sure if I have 8.8 ring or 7.5 ring rear.. Thanks

For the ring gear, the diameter of the bearings would be the same. The only way they would be different is if you had the 31-spline axles vs. the 28-spline (the 31s are bigger diameter). AutoZoo or any auto parts store can get you the right bearings.

As for what axle you have, research for "axle codes." You should have a code on the driver's-side door jamb sticker that tells you a code (84, F6, etc.) Once you know that, look for a chart that has what the code means. You'll then be able to find out whether you have an open or LSD; whether you have a 7.5 or 8.8 ring gear; and what your final drive gear ratio is. I'd also throw weight limits in there, but usually they're all 2750 lbs.

Either way, you'll also need to get rear differential lube. Depending on the use of your truck (DD vs. off-road, etc.) I'd get the proper weight and application lube.

By the way, an axle shaft seal should look like this:

http://shop.advanceautoparts.com/we...-seal-national_3271420-p?searchTerm=axle+seal

 

[luftwaffle]

Awesome, thanks man, I really appreciate your help.