Change or add transmission oil cooler?

[1997SCEBFEX]

++ on bigger pan. mine (Mag-Hytec) holds an additional 8 qts.

 

[Anchorclanker]

1997SCEBFEX. How much lower does your pan sit than the stock unit?

 

[coolzzy]

OD off and tow/haul are not the same. Tow/haul does not restrict the use of any gear, but it does adjust the shift rpm by holding gears longer before up shift, and aggressively downshifting on its own when acceleration is detected with no pedal input (rolling downhill). On the 6r80, 5th and 6th are overdrive gears, not sure on the 6r75.

 

[coolzzy]

A bigger pan can be a blessing and a curse. It does take longer to heat that extra fluid, but once it gets heated, it takes longer to cool as well. Since the cooling circuit is thermostatically controlled, you would be better served (especially financially and in ease of install) with just a larger cooler. These transmissions are very strong and failure is not a common thread, especially considering how many of them are on the road in other vehicles besides the expy.

 

[Anchorclanker]

Coolzzy. 5&6 are od on the 6r75 also. I run with overdrive on if its a flat road but otherwise od is off to avoid hunting on grades.

 

[Anchorclanker]

Update. I swapped out the cooler, 7 rows of fins instead of the original 5, which is a 40% increase over the stock unit. It reduced transmission fluid temp by roughly 7-9 degrees whie towing. It is enough make me feel more comfortable climbing the NC mountain roads. It's the Dorman 918-234 oil cooler and the only mod needed was to shorten the upper hose.

 

[ExplorerTom]

I swapped out the factory cooler on my 1st gen with a larger Hayden cooler. I watched trans temps still hit 200-215 in stop'n'go city driving in the summer with the AC on (maybe only 190-200 with AC off). It seemed that the cooler would get saturated because even driving highway speeds wouldn't cool it down.

Then I swapped the Hayden out for the BIG daddy cooler from a 6.0l diesel. Highest I've seen it since is about 185 while climbing a steep grade. But once I got passed that, it cools back down to about 150.

I know the transmissions are different, and I believe the 3rd gens are designed to run hotter, but I my opinion and experience, there is never such a thing as too much cooling for a transmission. The thermostats in the transmissions will regulate temp as needed- you just need to make sure there is plenty of cold fluid to send back in.

 

[chuck s]

Just a note from my personal towing with my (former) 2007 Expedition with HD Tow. YMMV.

I never locked out overdrive as the Interceptor gauge I mounted out of curiosity about transmission temps showed the transmission locked up immediately and securely in all gears, there was no transmission slip which is the culprit in many transmission overheating scenarios. Additionally since the transmission didn't "hunt" there was no need to lock out overdrive. Trailer is roughly 5000 pounds. Heavier trailer may be different.

I liked the Interceptor gauge and when towing I usually set it to indicate transmission temp and cylinder head temp. Transmission temp rarely exceeded 200°F, the "alarm" on the gauge was set at 220°F and only activated one (1) time in 10 years of towing and this was on a brutally hot day in city traffic. Only at that temp for a couple of minutes.

-- Chuck

 

[coolzzy]

I pulled my 29ft rv (6k pounds) up and over horshoe bend hill in Idaho this past weekend. It is a long 7-8% grade and I usually avoid it by taking back roads around. I had never pulled it with the new expy and will say she pulled like I was on flat ground. I went 65mph all the way up, passing semis and shocked diesel pickup drivers alike. Transmission temp was 206-208 on the climb, engine temp climbed a bit over normal by the time I hit the peak, I was in 4th gear for the climb except a short sting in 3rd when I had to pass a slow moving car.

I've pulled this hill with a 5.0 F150 (2012) and a 5.4 max tow F150 (2010 with 6speed). Both were labored but did the job, with the 5.4 beating out the 5.0 handily. Neither compared to the ecobeast expedition which managed the same task in silence and without any noticeable struggle. I think the stock cooling unit is more than adequate on these vehicles, although my 2012 F150 always ran hotter temps even with a larger cooler installed. Maybe some of these transmissions run hotter or have varying accuracy on their temp sensors....

 

[JExpedition07]

Coolzzy thanks for the feedback on your trip. The ecoboost likes to tow since it’s torque comes in early. I was under the impression the 5.0 was better at towing than the 5.4L as many 5.0 owners stated it was night and day. The torque curves speak a much different story with the 5.4L throwing more torque up to 4K rpm....curious if you ever ran E85 in the F-150 5.4, power was increased to 320hp/390 lb ft. on flex fuel. Curious if it makes much material difference in flex fuel capable 5.4 engines, MPGs surely take a hit on it. The 6 speed is thermostat controlled and it opens up to the cooler at a certain temp....as you stated could be set differently or accuracy of sensors.