Best of the Best Fluids?

Okie dokie... it's time to do tranny and transfer case fluids, will do the diffs when i regear hopefully in 3 weeks or so. What are the BEST fluids to use...forget the price, what is the very best fluids for AW4, 242, d30 with 4.56s, 8.25 w/ 4.56s. Also for engine oil? I have been using mobile 1 since i bought it 40,000 miles ago, but I have heard good things about redline fluids... anyone?
Vehicle Info, usage: 2000 XJ Limited, Tow Package (HD radiator, tranny cooler) it sees a lot of miles, and i tow a 4,000lb camper trailer in the summer, probably once every 3-5 weeks. There is roughly 85,000 miles on the xj...I'd rather pay through the nose and get the best, that's just how I am.

I changed my oil over to Mobil1 10W-30 Synthetic today in my engine and so far it runs nicely. I don't have any experience in the others(yet) but I have been told it's wise not to use anything but the recommended ATF for some reason.

- Kevin

Amsoil makes Mobile 1 look like piss. Anybody who uses Amsoil will tell you that...I am one of them. I suggest a good name brand non synthetic Dextron III in the transmission - the AW4 will last forever as long as you keep the fluid clean, and I have heard more than a few bad things about using synthetic in it. Chevron/Havoline makes some of the best Dextron III.

ZmOz said:

Amsoil makes Mobile 1 look like piss. Anybody who uses Amsoil will tell you that...I am one of them. I suggest a good name brand non synthetic Dextron III in the transmission - the AW4 will last forever as long as you keep the fluid clean, and I have heard more than a few bad things about using synthetic in it. Chevron/Havoline makes some of the best Dextron III.

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what made you change your mind about mobile 1. from previous posts on JU, you said mobile 1 was the best synthetic oil to use. are you an amsoil dealer? i dont doubt that amsoil ibetter, but what made you change your mind?

If the mobil-1 has been working for you stay with it. I think the filter is the important part. Better filtration longer life. I also prefer Mobil-1 due to availability, the only amsoil dealer here is a barber so it's tough to get on sun, mon and tues when he's closed and he always trys to sell you a bottle of clubman cologne and amway laundry detergent at the same time... Redline is also tough to find though I may try their MT90 the next time I change the AX15's lube, Mobil-1 in there now, been running it for the last 160,000mi in my 98. Have been running Mobil-1 in the diffs till I had the auburn installed in the rear, that requires a mineral based lube so there is Kendall w/friction modifier in now. Also been running Mobil-1 ATF in the 231 transfer case and thats been OK though it did find a weak point on the TC rear output seal and as a result keeps that area well lubed so I won't have to worry about any rust in that area, takes an ounce or two every 6 weeks or so.
Redoing the diffs gears soon, 3:07's to 4:10's, and will still use the Mobil-1 in the front diff, open open for now.
I emailed redline and Dave Grandquist came back pretty quick and said that the MT-90 is good in the AX15 so I'll give it a shot soon as I find a redline dealer locally. However I will have 4 quarts of Mobil-1 gear lube very handy if I notice anything funky going on....I plan on quite a few more years for this XJ.

89xj said:

what made you change your mind about mobile 1. from previous posts on JU, you said mobile 1 was the best synthetic oil to use. are you an amsoil dealer? i dont doubt that amsoil ibetter, but what made you change your mind?

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Mobile 1 is the best thing you can find off the shelf almost anywhere, but Amsoil is still far better.

So, as for clarity... What is the lube i should use in my 242 when i change it next weekend?

JeepinAudiophile said:

So, as for clarity... What is the lube i should use in my 242 when i change it next weekend?

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i use mobil 1 atf in my 242. made switching from 2wd-4wd smoother

I used mobile 1 Dextron III too. Again, I would have prefered Amsoil, but I already had a quart of Mobile 1. I didn't notice any difference, but I'm sure my transfer case likes it alot better than the brown fluid that wasn in there...

Red Line D4 ATF in the transfer case, Redline 75w90 in front & rear diff's
Good stuff

The synthetics were discussed in depth on- http://www.naxja.org/forum/showthread.php?t=26537