On, so I went with the ZF24 (if you don't know my saga already :)) - and was thinking of slapping a stock Auto cooler from the same transmission across the top of the roof/rear section (protected by the cage).

Would this be enough? or should I go with two? or should I go with a bigger one altogether (flat instead of long, with a fan?) - also, would I have issues with oil traveling up to the top of the cab?

Thanks.

Would this be enough?

If your radiator has the tranny cooler in it, perhaps. If this will be the only heat exchanger for your tranny, definitely not sufficient. Two would be better, but I'm certain there are other alternatives that could be easily sourced that would be more efficient in terms of physical size and thermal transfer.

A fan is almost always a good idea unless there are other considerations that those of us who do not travel in the desert are unaware.

Oil travel to the cooler-ain't gonna be a problem. If you're really concerned with flow rates, go with 5/8 or 3/4" hose. But, head:grinpimp: may be an issue now that I've thought about this a little bit. As this isn't really a closed system like engine cooling, you may run into problems with the level in the cooler above the level in the pan and this may cause you some issues. I believe you will need to keep the highest point of the cooler below the highest level of fluid in the tranny. You will certainly be increasing the volume of oil in the tranny with this system and when you shut the engine off, your oil may well flow out of the breathers onto the ground.

Remember the biggest danger to an autobox is heat and the inability to dissipate that heat. As the oil warms up, its viscosity lowers, thus reducing its efficiency. If you can increase the amount going to the cooler (or reduce any restriction to that flow) your performance should be increased.

Sounds like you're headed in the right direction with this project, keep us updated on it!

Peace,
PT

got the second biggeset cooler from Pep boys (I would assume you have similair generic auto parts stores) put it in front of my radiator and it worked fine for years towing heavy (which I think puts more strain than four wheeling) and offroading.

-ben

i used to have the standard 3.9 setup with oil running through the rad and then through the standard cooler. the oil got way too hot when offroading, so thats no good. i now have a 43 row mocal flat cooler in front of the rad and no oil flow through the rad anymore, the oil stays nice and cool now.

generally speaking, the bigger the better, especially when towing / offroading. good idea my be to get an old a/c cooler.