The bottom half of my diferential has oil all over it so im guessing i need a new gasket. Im not sure what axle i have. Is it a dana 50 or 60 or what? It has 12 bolts.
As for changing the fluid in it. What do i need to get and how much?

thanks
JAcob

 

I'm getting ready to do my 89 460 4x4 (12-bolt diff) and this is what I found:

Is it limited slip?: if so you need the LS additive
Oil: 3 quarts of 75-90 oil is just fine.
Plug should be in the rear, driver's side

 

I just used permatex for my cover. (good and cheap) Another thing to consider is if the cover is rusted through. I put a limited slip in my 250 and after I got everything sealed up, I noticed my tailgate was getting some oil spots on it. Frustrated I pulled the cover thinking that I didn't get it to seal properly after the limited slip. I really cleaned everything up this time and then reassembled. That night I saw a small dribble of oil going down my cover. Turned out to be a small hole rusted in the cover. Just a little heads up of another problem to be aware of.

 

how do i know if its limited slip?

 

The metal tag hanging off the diff should have a ID something like "4L10...."
meaning 4:10 gears with Limited Slip.

If it's not like this (mine is) than we'll have to have someone else explain how to tell which diff you have. There is a very high probability you have Limited Slip though. LS allows the truck to turn better. There is a whole other thread on Limited Slip (or posi traction, not sure that the thread title is).

 

OK i went out and looked at some stuff and heres what ive found. The front and back differentials have oily **** on them on the bottom. Do i need gaskets or silicone or what? Also where do i fill it back up? On the rear i found a screw thing but it looks liek its square. Where do i get a tool like that?
Also the tag on the back says 4.10 and a bunch of other letters and ****.

 

Jack it up and turn a tire. If only that tire turns you have an open diff or wore out diff. If you turn the tire forward and the other side turns backwards you have a limited slip. If both tires turn the same way you have a posi, or a spool. That plug is how you fill the fluid. Fill it until it is at the bottom of the hole. You can use a breaker bar or rachet with no socket to get it out. It should be a 3/8 drive. The easiest and cheapest way to do them is to use silicone. Get a tube from the parts store. That is what most people do themselves and shops too.

 

well......... A l/s doesnt help you turn. It's a traction aid, so when one wheel spins too much, it transfers power to the other wheel also.
For the gasket, just remove the cover and clean the mating surfaces very well and use a thick bead of gasket sealer on it.

 

Yes... chrono4, "well......... A l/s doesnt help you turn. It's a traction aid" I understand that. I guess I should have gone into it further (or not go into it at all) since L/S really isn't the topic of the thread.

I knew what I meant, I just said it wrong. oops.

 

OK my mom came home with a gallon 80w 90 gear oil and some silicone gasket stuff. Teh Gear oil will work right?
How do you guys pour into that hole? Its in an awkward spot on the side.

 

The gear oil usually comes in a bottle with a little spout and it should be easy enough to squeeze it in. When I first got my truck a shop had to replace some brake stuff so they had to remove the cover and they messed it up and it leaked. Got them to fix it again and it ended up leaking.. AGAIN. But when they did it it was only a minor amount. Just enough to look like a decent leak. Make sure you use a good amount of sealant and have the surface nice and clean. A small grinder works best.

 

Umm..this isnt in a bottle with a spout. Its a whole gallon. I guess ill have to rid something up.

 

Its the same thing..... easiest way to do it is to use a funnel with a hose on it. just make sure you have something under it to catch the lube that spills out when its full.