I can't decide whether to get a 5"x16" (light duty) or a 7.5"x12" (medium duty) cooler. My jeep is stock and staying stock, and I drive mostly in town.

 

heat kills
Get the biggest one you can afford/fit and your transmission will thank you for it

 

The bigger the better! Do the math and get the cooler with the largest volume

 

I thought so, thanks guys

 

What about in the winter? 20 below F is pretty typical here in MN. Wouldn't it also be bad for the tranny to run too cool?

 

If I were you, since you live where it gets cold, I'd keep your factory tranny cooler and run the auxiliary cooler "in line" with it. The coolant will help warm up the tranny fluid on cold days. You should be good to go like that

 

Just jumpin in on this but how exactly would you add it inline. I'm planning on doing this before this winter. I live in Illinois and it can get below 32 alot. I also plow with my jeep so I want to treat the tranny nice so she can stay happy

 

There's two hoses, one send hot fluid to the radiator, and another one send fluid back to the transmission.

This is the one u want to splice In the cooler, on the return line going back to the transmission.

 

Any idea which is which?


And I found a kit. 11x9 and the fluid flows through the fins instead of the copper pipe junk

 

Yep that one. If you're standing in front of the engine and looking down at the radiator, the line you want to splice is the one on the left. Also a way to tell, the soft portion of the line is located further forward on the return line.

See above. That's the style cooler I have. It will come with the brass fittings you'll need to cut and splice into the existing soft line of the return line.

 

Left? Both cooler lines are on the drivers side of the radiator. Top and bottom?

I spliced into the hot side metal supply line.

Cut the metal line, barb flared both ends and slid rubber hose over that and added a clamp. Done. Took 15 minutes with the radiator out.

The disconnected metal line in this picture:

 

Could you post a link to this? I'm looking for a good tranny cooler also. Thanks

 

I got mine from junkyard for 5 bucks then bought all hoses and fittings in a bag for 14.99 from pepboys

 

I just run a Hayden cooler kit from the parts store. It'll work just as well as any other.

 

Is it of any extra benefit to add a small fan to these coolers?

I'm going to be running 35's by the end of the year, probably on stock gearing for a while (not that I'll be driving it much like that), if that makes any difference...no threadjack intended. There should be a sticky on these tranny coolers!