differential fluid change/trans fluid change

[sharky88]

diff:whats the mfg rec'd amount and weight? 90 w? the sealant that was last applied to the cover is intact no leaks so i just want to change the fluid anything special i need to know/have on hand?

trans: dexron3 seems to be the fluid but is 5 qts correct on an 88 auto 4.0l?
mech said to change it every other oil change....good advice?

[89xjSportDave]

to drain all of the diff fluid you have to remove the covers. I just did mine (89 Cherokee Sport 5spd 4.0l) last week. each diff takes approx 1.25qts but just fill it until it starts to run out of the fill hole then stick your finger in and get a little more out. I used "The Right Stuff" by Permatex and it worked great to seal it. I used a 75-90w in mine. Make sure you clean the gasket surfaces really good and if its a limited slip rear end (mine isn't) you have to add I think 2 oz of some special lubericant but I don't remember what.

[theNomad]

Use any 75W-90 gear oil.
If you feel the need you can use the synthetic or redline etc. I used regular dino oil.
What I did to change bother the front and reaf diff was to buy the cheap plastic pumps they sell at auto stores that go into gallon jugs and use that with a length of silicone hose on the end. I stuck the hose into the diff and fed it all the way to the bottom and pumped all the old crap out, then pumped/poured the new stuff in. Easy 30 min job, or less if you're fast.
I didn't feel the need to crack open the cover, next time I will and I'll clean out the pumpkins etc. For now, I'm just fine as is.

[sharky88]

thanks. my xj was just burglarised in my garage!2 windows and 5 years of my hancrafted art and alot of photos i sell gone. might just have to sell the xj to get started again. i am so sad that the xj just sits empty violated and undriven as driving it causes me get sick :O( will do diff when i can thanks for the tip.

[kevinmcf]

I use lucas oil supplements my last 87 jeep had over 300,000 mi and ran great, the weekest part in drivetrane is the transfer case. Change fluid once a year will insure good life. Can use regular dextron or as I have mixed with lucas trans. additive. My 1990 jeep currently has 215,000 mi
(although the motor was replace, cooked it real bad once).