Differential Fluid Change Questions

[fony3]

Ok, first question, how much gear oil am I going to do need for my two diffs? Its a 30 and 35 combo if that matters. Second question, do i just fill it up till its starts to leak at the plug hole?

Cheers!

[SwampSinger]

Ok, first question, how much gear oil am I going to do need for my two diffs? Its a 30 and 35 combo if that matters. Second question, do i just fill it up till its starts to leak at the plug hole?

Cheers!

You'll need about 3L for both (get a 4L jug ...it's cheaper) and yes... fill it till it spew out.

have fun

[RckyMtnTJ]

Both are a little over a liter.  If your rear has a traclok, you will need fluid for limited slip.   Either that or friction modifier from Mopar.  Get yourself 3 liters and you are good to go.  Just fill it till it starts to come out the fill hole.

[fony3]

No fancy traclok here...Thanks for the info guys! Any recomendations on the gear oil and RTV to used?

[BlackYJ]

I use standard 80w-90 gear oil for the diffs, quaker state i think, and the ultra black is good RTV because it is resistance to oil, but it is pricy.  I have also used black rtv and is works fine.

Install note - make sure the mating surface is FREE of any oil as oil will prevent the rtv from sealing properly.  Brake cleaner works great to clean off the old sealant

[RckyMtnTJ]

I use the Canadian Tire brand gear lube.  They have a synthetic version too.  I typically change my diff fluids a couple times a year if not more, so I find the Canuck Tire version works well enough.  I second the cleaning of the mating surfaces that BlackYJ was mentioning.  I tend to scrape off the gasket on the diff as good as possible.  Then I wire wheel the diff cover to get it all off.  Never had a problem.

[fony3]

Ok, I have everything i need except a Gasket Scrapper...where do you think I could get one. Crappy tire didnt, maybe part source?

[BlackYJ]

Ok, I have everything i need except a Gasket Scrapper...where do you think I could get one. Crappy tire didnt, maybe part source?

Just get a razor blade or even a good chisels and don't forget brake cleaner

[rws]

A wire wheel on a drill works good to remove old sealant.  Some people will also spray the insides of the diff  with brake cleaner to remove all old fluid and metal flakes.

[fony3]

Beauty...thats what I was gonna resort to (razor)...one last question, how much RTV am I going to need. Is one squeeze tube gonna be enough, or should I get two.

[bae146]

I usually clean up the cover first and then spread a thin layer of rtv over the cover and set aside while I clean out the diff and the mating surface.  This gives the sealant on the cover time to skin over.  It is still tacky but a little thicker than when it first comes out of the tube.  This works for me.....

[rws]

One squeeze tube will do several differentials. Go around the bolt holes and don't  over- tighten the cover bolts. One more tip - if possible, after reinstalling the cover do not put gear oil in till the next day which allows the silicon to dry.

[BlackYJ]

The RTV bead only needs to be about 1/8"-1/4" wide

[fony3]

Great thanks for all the advice!

[fony3]

Ok, Finally got some time to start on the Diffs. I am having a bit of trouble getting the old gasket off, am i just not trying hard enough? I think tomorrow i am gonna go pick up a can of gasket remover. Also I am wondering if i can/should do something about the rust on the cover and carrier? Everything else seems to be in good shape.