I have a 2006 Mega-Cab, 4X4 with the 5.9 liter TCM engine.
I have had the overheat indicator come on twice since I have owned the vehicle.
Once was I was towing a 7,500 lb toy hauler in a snow storm (outside temp in the high 20's), I was in 4 wheel drive going up a long hill (dirt road) with chain on all 4 tires. The transmission overtemp light came on near top of the hill. I put the truck in neutral and idled till light went off.

I did a transmission flush after that incident.

Second time was over Thankgiving 2008. Pulling a empty flatbed trailer (3000 lbs) Up hill (steep hill was a intermediate ski slope), in 4 wheel drive, as I approach the top of the hill the transmission over temp light came on, I put the vechile in neutral and idled till light went out.

I would like to add a extra transmission fluid cooler. Any recommendations.

Banks Engineering said its cause the transmission is not locking up (too much load?) They want to install a torque converter that locks up earlier (so less heat is generated) Any opinions on this option.

Should I drive in different modes 4 high, 4 low, Tow option on, or O/D off.

 

I not a transmission specialist by any means but I would consider calling Goerends or any of the other big name tranny guys before I bought anything from Banks..


If your going up steep grades at low speeds try manually shifting into 2nd to lock up the T/C. Tow option will also help a little. An oversized tranny pan will also help cool down things down. Also beware of backing heavy loads for long distance for this to will heat up the tranny pretty quick

 

Goerends all they way! Also if it was me I would use the tow haul mode.

 

A tighter TC will generate more heat in the conditions you talk about, less heat on flat acceleration.

Unless you use a lockup controller you cannot control lockup with just a replacement TC.

Manually downshifting to 2nd and a lockup switch in those conditions will be your best bet, dirt cheap, and much more effective than a TC.

 

Forget a cooler. I;d PM Tim Holt.........I've had great success with him.

 

I agree with annabelle. Tim is usually at www.dieselram.com. You already have two tranny coolers. Water to oil and air to oil.

Pete
(xploretx)

 

DBLR has told you what you should do. Try this it should work. If it does you can save your money---GOOD LUCK

 

Isn't there some kind of rubber check valve in the transmission line that many people remove??? Seems to me I read on one of these forums about such a valve and guys remove their lines, drill a hole in the rubber and pull it out piece at a time. I think it is because if it fails to open you get less flow out to the coolers!! Check this out, I may be dead wrong!!