I have walked out twice to find oil on the driveway coming from the rear passenger wheel. I checked both the brake and diff fluid and they seem to be at operating capacity. Any ideas?

 

pull the wheel off - I bet you will find the outer diff seal leaking. Time to replace it or the rear shoe will lock up.

 

how hard is it to replace a rear diff seal on these trucks?

 

Dont know...mine went out when it was -33...so I had to get a mechanic to do it for me.

 

There are only 2 fluids back there, gear oil from the diff and brake fluid. When either one is leaking you must remove the drum and check it out and repair it. The newer trucks have outboard drums and can be removed without removing the hubs. If you replace the seal, ask the parts man if you can get a seal driver to install it. If the shoes are soaked, it is best to replace them. Eliminates a lot of potential problems.

 

you have to pull the axle to replace the seal

 

TEXWS6 it's not too hard to replace. i just did my right rear seal this last weekend.

you need to go to NAPA or somewhere and get a new seal. i think mine was less than $10 for my 96. you'll need to also get a rear axle hub nut socket. this cost about $10 too. (mine didn't fit so i had to customize the process. PM me if you can't make it work) you'll also need some diff fluid and some friction additive if you have a limmited slip as some oil will drain out in the process. to minimize this, jack up the side that is leaking and put a heavy duty jack stand under it so that it is tilted up enough to get the tire or tires off.

once you get the tires off you will need to get the drum off. this can be a process in itself. use a BFH and "tap" around the drum to losen it and pull it off. you may need to use a flat blade screw driver to losen the brake shoes.

once you have that off. you will need to take the socket that you got and take off the hub nut. there it a little retainer on the nut that you will need to remove before taking off the nut.

once the nut is off, take the hub off and slide the axle out.
pull the seal out and clean the area. put the new seal in and reverse the process.
when putting the hub back on, make sure that you tighten the hub nut enough so that there isn't slack in the bearing and the hub spins freely. you can count the rotations as you take it off too to get a good idea. feel the hub too before you take it off to get a feal for that.

i'm sure that you have a mess back there so you will either have to do a brake job yourself or take it in. if you do it yourself make sure to get a couple bottles of brake cleaner. you will get very dirty
hope this helps.

-Bryan

 

what and how much fluid do you recommend to refill the differential?

some people say not to add friction additive, does it depend on the lube you use?

 

i just got a quart of conoco diff fluid and i haven't put the friction additive in yet but i'm going to pick up some lucus stuff from NAPA.
you really don't lose that much fluid, about a half court so friction additive is not crutial.

 

do all models come with the limited slip rear end?

 

it will tell you on the tag at the top of your diff cover.

 

will it be that obvious when looking to see if it is a limited slip rear end?

i bought some Penzoil 80W-90 with friction modifier already in it, will it hurt to add if i don't have a limited slip rear end?


thanks,

Kelly

 

it will say limited slip on the metal tag.
i don't see why it would hurt to put the 90 wieght in w/ the modifier. the ring and pinion in both are the same and i'm sure it wont hurt the spyder gears if it's not a LS diff.

 

That is pretty much how it goes , except the axle has to come out before you can loosen the hub nut etc , and if you can't get the drum off because it is rusted to the hub , leave it , when you loosen the big hub nut and take the hub off ,the drum will come with it, you can tap the hub out with a hammer and a block of wood later.

 

Do it the easy way and save yourself much time beating.
Put your rear end up on jack stands, remove the wheel(s) and put one lug nut back on loosely, start engine put it in gear and slam on the brakes in forward and reverse. You will here a loud pop when the break loose. Gets them loose every time, I haven't beat on drums with a hammer for years.

I prefer to use a rear end lube with no friction modifier on a LSD differential so I can add the exact amount myself. Too much friction modifier and the clutches slip, you will have a non posi-traction rear end. There is no set amount of friction modifier to use, it all depends on the brand of lube oil you use and the amount of wear on each individual truck's clutch pac.