Is tranny cooler necessary for towing?

I'm thinking of buying a class III hitch in order to tow a U-haul trailer and wanted to know if a transmission cooler is necessary. It's cheaper for me to rent a trailer than rent a truck and tow my Jeep behind than if I get the hitch, plus the hitch will be "forever".

I have a '99 Cherokee with 97K miles, and the move will be from Georgia in October. Any advice would be appreciated.

How far are you going and how much weight are you towing?

If its Georgia to North Carolina, I'd get the cooler. You can buy a B&M stacked plate cooler for about 50 bucks, and they're relatively simple to install.

Cheap insurance if you ask me.

Total distance would be 365 miles. Since I'm already buying the hitch I was trying to limit other expenses. I have an AW4 thats already hooked into the radiator (which is a new 3-core)), I just wasn't sure if another cooling option was required.

According to Uhaul the trailer is 2,800 pounds fully loaded.

Is it absolutely required? Not necessarily (I drove ATL to SJC in a 1989 Limited 4.0/AW4 with a 3500# U-Hell Box without a cooler...) Is it cheap insurance? Yes!

I have found that the AW4 is a rather solid slushbox (from what I've beaten them into, and a couple of postmortem analyses showed that the transmission failing wasn't the transmission's fault) - and surprisingly tolerant of heat and stress. However, it's always good to keep your automatic transmission cool (HEAT IS THE ENEMY!) so I'd put one in anyhow.

While I was about it, I'd probably also put in a "remote spin-on filter kit" - the AW4 sump strainer is exactly that - a strainer. It's just a bit of screen that catches large stuff, and I only pull the pan every third fluid change or so to clean the magnet and check the screen. I just haven't gotten around to installing a spin-on filter myself yet...

If you're just going to do occasional towing, say, under 2,000# or so every few months, I'd probably not worry much about it (the ATL-SJC trip was a one-shot deal.) If you're going to do it frequently, get a cooler and consider the remote filter setup.

5-90

First place to look is your owner's manual. My 88 XJ owner's manual says you need to have the Aux trans cooler if you are towing over 2000 lbs.

Second you have to ask yourself if you want to go on the word of others and hope you do not damage your vehicle or do you follow the manufacturer's requirements. With newer vehicles the service intervals are extended to make it seem "cheaper" to own. A lot of people continue to change engine oil, change spark plugs, etc at shorter intervals because they feel better at that interval. With that said why would you "chance it" by not installing an aux cooler?

I installed the Jeep Aux cooler, purchased it at the dealer. I liked how it dropped in and connected up with no hose cutting. I do not know what the dealer kit costs now but compare before you buy.

Also how long ago did you change the transmission fluid in your transmission? You may want to do a change before you tow so you have fluid that is not degraded. Take a lesson from my experience and do NOT use synthetic AFT in your transmission, just use the fluid called out by your owner's manual, Dextron is my guess. When I pulled the pan off my AW4 and I had a paper filter installed, no screen. Someone had the fluid changed before I picked up my 88 XJ with 97K on it and IF it had a screeen it was replaced with your normal paper trans filter. Also with the AW4 you can pull the drain plug and drain out 3 quarts of fluid, you could do that a 3 or 4 times a few days apart and you will end up changing out most of the fluid.

You may also want to change the lube in your rear differential before you tow. My owner's manual says if you are towing to use 75W-145 Synthetic gear lube.

Only you know if you are current on your maintenance and you know how long you plan to own the vehicle.

Dexron II/III is what the AW4 likes - and NOT synthetic! I've not heard a good report from the field on synthetic in the AW4 yet - the synthetic fluid allows too much clutch slippage.

I've not seen a paper filter in any AW4 - the three I've got have had screens, the ones I've seen that other people owned have screens, and all the aftermarket filters I've seen are screens. Still, it's good to pull the pan - you can also clean the sump magnet that's in there to collect any iron/steel bits that collect - and it's going to be fuzzy if it hasn't been cleaned yet. You won't find much after that, but it's good to check it at intervals anyhow (I pull the pan about every third change...)

5-90

I recommend you have one just to be safe. I installed a OEM one that I got and it works great. Not that hard to hookup and mount.

i got one on my 99 and i don't even tow. but then again i had an automatic on a different vehicle fail years ago and i vowed never again.