Transmission cooler

The problem with overcooling comes when you don't do any towing for periods of time in cooler weather. The transmission needs to warm up occasionally to cook of moisture for condensation. The 4R100 does not have a transmission thermostat like the TorqueShift. Only a pressure bypass valve, which should only open in very extreme cold temps (well below zero).

I installed the Tru-Cool Max 40,000 cooler in my van. When I'm not towing, it never goes above 140F in the winter. I used to block the grill during the winter to help the transmission stay warm, but now I don't need to since its used almost exclusively for towing now.

I do have 4.56 gear and highly recommend them for towing heavy. My tire size is 265.

If you have the V-10 then you have the medium sized trans cooler, the 7.3 EXs had the small ones and the 6.0 rigs got the nice big ones. Between the radiator cooler and the air to oil trans cooler you should be OK, we have towed 30k+ miles on our stock v-10 cooler and only been over 200 degrees a couple of times briefly. If you want to upgrade to the 6.0 cooler you should be fine, expect to see cooler temps but I doubt that you will suffer any issues from over cooling with it.
Changing the gear ratio will not affect the speedometer reading as the speedo gets it's signal from the ring gears tone ring, so the speedo only reads axle/tire revolutions, gears don't change that reading. changing tire size will affect the speedo readings and to an extent can be corrected by computer recalibration.
All EXcursions came with factory trans coolers, only very early '00 models lacked the cooler in the radiators, if you have that setup you would benefit from a radiator upgrade, it does a lot of the cooling work.
All Excursions also came with the rear receiver tow hitch, it was part of the federal crash gear required due to the EX being a station wagon vs a truck. EXs with the "Heavy Duty Towing Package" actually didn't get much in the way of upgrades, same hitch, springs, radiator, trans cooler and engine output. What you did get was the larger extendable towing mirrors and on later rigs a rear sway bar, the package was available with both the standard 3.73 or the optional 4.30 (this is for the V-10 rigs only, all PSD EXs came with 3.73 gears) gear ratio. I agree that if upgrading from the 3.73 gears don't go to 4.10, go to AT LEAST 4.30 if not 4.56 gears. These motors make their best power at higher revs so they love deeper gears. I ran my V-10 EX with 4.88s and stock sized tires for 2 years and it towed like a locomotive! I now have 35" tires (vs the stock 31.6" tires) which gives me the effective 4.39 ratio that still tows our 11,000lb TT very well.

noonenosthis1 wrote:
I've used the Ford Truck VIN decoder. I have a class IV towing package. Doesn't say if that includes a transmission cooler. Some have said that it does include the transmission cooler but those are small. Some have upgraded to a bigger cooler. I'm thinking along those lines. Our Ex is a 2000 Limited. I love her!

If you are within the tow rating the transmission will be fine. All have a cooler in the radiator. If it has an auxiliary cooler it will be part of the front stack as a small radiator. This can be discovered by physical inspection.

Just drive normal and avoid gear hunting and you will be fine. Going 3.73 to 4.10 will only help cool the transmission. Honestly I would go right to 4.30 or 4.56 ratio if spending money. You may also need a computer update to correct the speedometer.

noonenosthis1 wrote:
She's a gasser. How do you overcool? What would be the result?

If you cool the transmission below normal operating temps. It will not shift as it should. It may not even go into high gear. My transmission has a thermostat. It will NOT let the trany change to high before it reaches a certain temp. It only works correctly at the proper operating temp. Cold fluid doesn't flow very well.

She's a gasser. How do you overcool? What would be the result?

Diesel or gas?

-You probably would benefit from a larger cooler with that much trailer. But it is very possible to over-cool the 4R100, especially with the V10.

-If you have the V10, skip the 4.10s and go straight to 4.30s. That'll be a jump actually worth making. 4.10s with either motor will hardly be noticeable. With the diesel, I'd say stay with the 3.73, and use the $ to do some minor performance upgrades instead. A free flow muffler and larger air filter (biggest NAPA paper one that will fit) will do more than gearing in the diesel. But with the V10, gears are everything.

theoldwizard1 wrote:

noonenosthis1 wrote:
I've used the Ford Truck VIN decoder. I have a class IV towing package.

Then you have a cooler and probably a HD radiator.

And I repeat if its a 7.3 he would be better off with the 31 row 6.0 transmission cooler.

marcsbigfoot20b27 wrote:

Kalabin wrote:
Depending on the model of Excursion it comes with different sized transmission coolers I believe. My V10 has a 10 row cooler, and I am looking into swapping it out for a 6.0 cooler (32 rows I believe). I had my transmission up to 230 a few times this summer crawling up twisting mountain roads.

If you add the 30+ row (6.0 diesel cooler) you will never see over 170 degrees ever!!
I live in Phoenix and we have some nice size mountains between here and Payson and the Rim. Even coming home and towing 7.5K 75 mph up the big hills in 105+ degrees I never ever see over 165-170. It is the best oem bolt ons that should have been there from day one.

Good info! Yeah I'm hoping to have it done prior to our first tow this next camping season.

noonenosthis1 wrote:
I've used the Ford Truck VIN decoder. I have a class IV towing package.

Then you have a cooler and probably a HD radiator.

Kalabin wrote:
Depending on the model of Excursion it comes with different sized transmission coolers I believe. My V10 has a 10 row cooler, and I am looking into swapping it out for a 6.0 cooler (32 rows I believe). I had my transmission up to 230 a few times this summer crawling up twisting mountain roads.

If you add the 30+ row (6.0 diesel cooler) you will never see over 170 degrees ever!!
I live in Phoenix and we have some nice size mountains between here and Payson and the Rim. Even coming home and towing 7.5K 75 mph up the big hills in 105+ degrees I never ever see over 165-170. It is the best oem bolt ons that should have been there from day one.