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Aw4 power handling/ reliablity and performance upgrades.

Keep in mind that higher pressure requires more power from the engine and raises fluid temps. If you want faster shifts with no power loss or additional heat gain you need to modify the separator plate.
 
Does anybody know what kind of fluid the a stock AW4 with 200***miles will like the most?

I know people like to avoid synthetic motor oil with higher mileage engines altogether because they say it will make it leak.

Is this theory or has it been proven?
Does this play in at all with transmission fluid?

1996 XJ Country 4.0, AW4, MP231, 3in Rough Country Lift, 31in Sailun Terramax on Crager Soft15x8's​
 
FWIW, I use Amsoil Universal ATF in my AW4/231 and soon to be 242.

You can do the "poor man's flush"

As far an syn fluid goes. "True" syn fluid molecules are the same size. The fluid does not make stuff leak. If something is leaking it makes it more noticeable.
 
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when I bought my 99 xj the next day I put a new tranny cooler on it. I had a spare one in the garage, and noticed the factory one was a joke. after you own a cummins truck you tend to look for tranny weakness on every vehicle you own after that. lol
 
I used the junkyard site car-part dot com to find a 2003 Lexus IS300 transmission at a junkyard near where I live for $85 plus refundable core charge. A steal.

1. The pan is a direct replacement for the AW4 pan with the following differences:
A. The dipstick tube is on the other side of the pan and the way it is bent for the Lexus interferes with the Jeep bell housing. I'm sure it will work after some modification but just FYI
B. The pan is 4mm (5/32") deeper on the deep end (no clearance issues for me.)
C. It holds 790 ml (.83 qt.) more fluid than the AW4 pan (not as much as I had hoped but every little bit helps)

2. My intention is also to swap the pump from this trans into the AW4 as I am told it is a direct fit and 25% higher capacity.

Happy trails.
 
There are 2 threaded holes in the transmission pump that allow the pump to be pulled out. Does anyone know the thread size on those. I'm not doing too good on guessing.

thanks.
 
There are 2 threaded holes in the transmission pump that allow the pump to be pulled out. Does anyone know the thread size on those.

After multiple trips to the store, I learned that the thread size of these holes is M10 with a 1.25 pitch.

Now if I could just get the pump to budge!
 
You're supposed to use a slide-hammer type of attachment like with GM transmissions. (one in each hole)
Look into renting a slide hammer from an auto parts store or go to harbor freight and get to and take one back later..
On going back together, you can get one of those wire lip seal installers.
It's a simple metal pipe with a thin tough wire looped around and crimped back in the end of pipe.
You use it like a kind of 'shoe horn' (and a lot of lube/assembly grease/vaseline.) and slide the wire end around seal to bend the lip back in so it won't get cut by the mating surfaces.
EVERY trans shop knows what they are..

Errol
 
SUBSCRIBED - great thread!
 
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