Gearbox Cooling

Mike1 · #1 (**permalink**) 02-05-2004, 08:55 AM

Hi

I have a 98 Cherokee Country 4.0L automatic. The car is running in hot conditions around 33 degrees centigrade. I was told that the cooling of the gearbox was via the radiator water, as it doesnt have a seperate gearbox oil cooler. I tow around 600Kg's regularly.

Is the standard set-up sufficient or is it a necessity to fit a seperate gearbox cooler?

If so what are the recommended specifications, or is there a standard modification that can be purchased?

Michael Schroder (South Africa)

Bounty__Hunter · #2 (**permalink**) 02-05-2004, 01:52 PM

Install an external tranny cooler like the ones that came on XJ towing packages. Check out the local auto parts stores and you'll find one to fit your needs.

XJNick · #3 (**permalink**) 02-05-2004, 05:35 PM

Hi,

You probably have a dual purpose radiator that has coolant flowing through it on one side and the Auto Transmission Fluid on the other, or such.

Make sure your mechanical clutch fan (if applicable) is functioning properly and that the electric fan is coming on ANYTIME the A/C is running or the coolant temp gets above ~210 degrees F.

Keep in mind that 210 degrees F. is normal operating temp.

-Nick

Mike1 · #4 (**permalink**) 02-06-2004, 05:51 AM

Hi Nick

Mechanical clutch viscous fan is working 100% and electric fan comes in with a/c

However our conditions in South Africa are allot hotter than in America. Will the auto box be OK under high temperature and towing?

Thanks Mike

Bounty__Hunter · #5 (**permalink**) 02-07-2004, 06:49 AM

Heat kills auto trannies, use the external tranny cooler. It's possible to double the life of an auto tranny by getting rid of the heat.

Tug-n-pull · #6 (**permalink**) 02-08-2004, 01:24 AM

Hey Mike it may be a good idea to add an additional electric pusher fan on the front of the grill in addition to an external cooler to the tranny. In the conditions you drive under any extra will be a great help.

The other point I would like to make is Welcome. Great to have you here with us. Big ol Jeep Wave to you from the hills of North East Tennessee! tug :wink:

Bounty__Hunter · #7 (**permalink**) 02-08-2004, 05:03 PM

Good idea, Tug, the external cooler will help and a pusher fan on that cooler would help even more.

How hot are your average drives, in F degrees?

Junkpile · #8 (**permalink**) 02-08-2004, 08:00 PM

Yes, you need to add an external cooler if you are going to be towing and it's not a bad idea even if you aren't.

Make sure you aren't under-geared. That puts more of a load on the tranny and will cause an automatic to run hotter and wear out faster.

I would assume that a 98 would require computer modifications to change shift points and shift firmness, but that will make an automatic tranny run cooler also. A "shift kit" is actually very beneficial to an automatic transmission, the fluid and friction surfaces won't get as hot because you reduce slippage between shifts by engaging them faster.

Mike1 · #9 (**permalink**) 02-09-2004, 12:50 AM

Hi

Thanks for all the great advice

Thanks for the welcome TUG much appreciated

It would be a great help if someone could point me in the right direction on where to purchase a tranny cooler including hoses connectors etc. for my 4.0L auto. Prefurably a reputable dealer due to the distances involved.

Is the tranny cooler mounted upfront on the jeep before the radiator? What is the best place?

Regards Mike(SA)

Bounty__Hunter · #10 (**permalink**) 02-09-2004, 08:06 AM

Mount it in front of the stock radiator if space allows. Be a tight squeeze on an XJ to get a pusher fan in there too but it may be possible.

Click HERE for tranny coolers. There are some that come with a fan for around $135 USD.

I've ordered from them before with no problems.