[billabongopblue]

Hey everyone,

I want to replace all the fluids in my XJ. Being new to cars overall (as this is my first car) i only know how to change the oil which i did.

I know all need to replaced, I just don't know were all the fluids are located. All i know of is oil, transmission, brake.

If you could be kind enough and list all the fluids that would need to be changed (which should be all besides oil) that would be great. Along with what they should be replaced with, as in what brand and viscosity etc.

Thank you all for the help.

[jjg214]

front and rear diffs, the pumpkins on the axle. you have to remove the cover to drain, then use RTV to make a new seal and let it dry, then refill up to the fill hole, 75-90 gear oil is spec. i used mobil 1 i believe. 75-140 if its a heavy duty trail/towing rig.

transfer case fluid, drain it with the drain plug, fill it with the fill plug. they are 30mm sockets on your year IIRC. put whatever you put in ur tranny in the t-case.

[TreddyoXJ]

Radiator fluid, differential fluids, transfer case fluid, transmission fluid, and brake fluid are all fluids that you can replace. The radiator fluid is located (hence the name) in the radiator and in the motor. You can replace the radiator fluid by removing the lower radiator hose and just doing a drain and refill, or you can take it to a shop you trust that has a coolant exchanging machine and have them replace all of it.

The differential fluids are both GL5 gear lube. The differentials are the pumpkin looking center sections of your front and rear solid axle housings. Most multi-grade viscosities will work. Conventional 80W-90 will suffice unless you have a differential that is limited slip or "trac-lock" as Jeep calls it. This will requite either a synthetic or an additive specifically intended to condition the parts of the limited slip so that it will work properly. You can use a larger range viscosity (i.e. 75W-140) if you tow are put larger amounts of strain on your vehicles differentials. It's not necessary, though if you don't want to spend the extra money.

The transfer case will probably take an automatic transmission fluid such as Dextron III/Mercon. You'll need to check the tag on the transfer case to see which model number it is and what fluid it subsequently takes. The transfer case is attached to the back of the transmission and has two drive shafts coming off of it going to the front and rear differentials.

Assuming you have an AW4 automatic transmission, it will take 3 quarts of Dextron III/Mercon ATF fluid if you just drain and refill it.

Replacing brake fluid isn't really a high priority most of the time, but it can get dirty and need to be replaced. Most people just do this around the time that they do a brake job as it makes more sense. They basically need to be bleed until the new fluid that is being added starts coming out the bleeder valves.

[billabongopblue]

Thank you all for the help i appreciate it.

[conrasm]

A little tip on the changing the transfer case fluid. Make sure you try to loosen the fill plug first, since that can be the harder one to get loose. That way you don't drain all the fluid and end up not getting the fill plug loose to fill it up again.

The differential fluid change is messy. Have a lot of paper towels and rags handy.

Buy yourself a grease gun and lube the steering and driveshaft fittings while you're toolin around under there. The front shaft has a fitting to grease.

[Mean Max]

This may help.

AX-15 tranny drain


AX-15 tranny fill plug


NP 231J transfer case drain & fill plugs.


And here's some differential gear oil change info.

http://www.jeepforum.com/forum/f12/basic-diff-lube-maintenance-728231/

Max

[nujeepguy]

my 231 transfer case takes a 9 or 10 mm (can't exactly recall)allen wrench it isn't 30mm hex. so take a look on yours to be prepared.

[Mean Max]

Originally Posted by nujeepguy

my 231 transfer case takes a 9 or 10 mm (can't exactly recall)allen wrench it isn't 30mm hex. so take a look on yours to be prepared.

True enough, some NP231's (especially newer than my '91 YJ) have 10mm, and some others have 17MM, allen head drain & fill plugs.

I should probably update & include that info on the pic.

Thanks!

Max