Well I just bought a 98 jeep Cherokee 4.0 with 243k miles and had a bunch of questions about it. I plan on changing most of the fluids on it because of the high mileage and this is what I bought so far

Diff fluid: Mobil 1 75-90
Transfer case fluid: carquest (rebranded valvoline) dex/merc
Engine oil: carquest 5w30 synthetic
I also got NGK spark plugs

My first question is, how particular is the Cherokee on what fluids are put in it? I only ask because I'm coming from a STi where it didn't like certain fluids.

Would it be bad to change the trans fluid on a Cherokee with that many miles? I've heard stories where people have change transmission fluids on high mileage automatics and it caused them to slip

Would it be bad to seafoam the engine and induction systems with the mileage this jeep has? I recently did it on my STi (72k miles) and it made it ran a lot better.

Is there anything else I should change on this before I start to build it?

 

Looks like you're off to a good start. I would definitely change the tranny fluid and filter. Just don't use a pressurized system to 'flush' it. High pressure flushes can blow out seals, hoses, etc on high milage auto trannys. A simple drain and fill method should be fine.

 

If its an automatic, for the transmission i would drain the fluid and change the trans filter. Your only going to drain about 2 quarts from the trans, the rest isn't going to drain because its in the torque converter. So its not really going to cause harm because your not really changing all the fluid, your basically diluting it. I wouldnt take it to a shop and get it all flushed out and new put in because that could be bad for the tranny at that mileage.

 

Don't power flush it, as others have mentioned...and don't switch to ATF+4. Stick with the Dexron.

 

.....the cooling system? Is the glove box full of maintenance receipts?

 

I would do that normally but it just a new radiator and hoses put in

 

Your list of fluids look good. As mentioned, change the fluid and filter in the tranny, but do NOT flush it. And I'd say go for the seafoam. I'd only do it through the gas tank and the intake (not in the oil with that many miles)