Okay, I THINK I got a definitive answer about Mopar power steering fluids. After a long discussion with my dealer's parts manager and scanning his computer for a while, we came to the conclusion that my '00 WJ takes MS-5931 (P/N 04883077), a clear fluid. The system with the hydraulic fan takes MS-10838 (P/N 05142893AA), also a clear fluid. The systems without the hydro fan after 2002 take ATF+4. How confusing can they make it?

SO, now I have to purge my pump of the 10838 and refill with 5931. He said he didn't think I'd have any problems because of the short time, but he didn't know for sure. He also will talk to his counter guys about making guesses and assumptions without checking. He stressed that his guys don't very often work with "older" vehicles. I can see that because this is a "rich" town.

Do you know why the east side of any major city is "fashionable?" It's because when commuting, the sun is always behind you. Fact.

 

Is the 10838 the stuff you bought for 7 bucks a quart? It's much higher here.

 

Yeah, I made a mistake. It was $9.95/qt. The ATF+4 was $7.50/qt. (for my trans)

I just bought an oil pressure sensor for $75. ($81 with tax)

 

Okay, listen to this. When I bought my WJ, it had 128K on it. The PO had the power steering pressure hose replaced at 125K. His mechanic put ATF+4 in it! So for the past 35K it's had the wrong fluid in it!! The dealer guys said these systems are pretty rugged and just about any P/S fluid would work, although they wouldn't recommend using anything other that Mopar fluids. Of course they'd say that!

I guess that answers the question about P/S fluids, doesn't it? My pump whines a bit on cold startup but quiets pretty quickly with the MS-5931 in it.

 

You don't have the hydraulic cooling fan. You can use generic p/s fluid. Put that stuff in one with the hydraulic fan and listen to it scream and watch it over heat. I would not even pull mine out of the garage with the wrong stuff in it. Just drained it and waited for the dealer to open so I could get the right stuff.

 

That hydraulic fan is a hydraulic motor an requires a hydraulic fluid that will absorb the heat and not break down. It also needs lubricity because of the motor's vanes rubbing on the side of the motor housing. I'm assuming it's a vane motor because a gearotor motor is designed for low speed torque. It specifically needs a hydraulic fluid.

IMHO, it's the worst mistake jeep ever made. The intention was to lessen the load on the electrical system.

 

Yep, that hydraulic fan is a turd alright. I believe if you try to swap in a electric fan it throws a code and causes all kinds of problems. Wish I did not have it.

 

There's a problem for our electronic gurus to work on. Someone suggested leaving the solenoid connected to the harness and bagging it, making the PCM thinking it's still working. IDK but I think the answer should be a simple one. I, myself would think using the pulse-width modulated relay from the 2000 electric fan system in the 4.0 would work. It's basically the same as the valve in the hydro system.