Aux. transmission cooler and/or larger oil pan update?

[daveb]

So you guys are saying I'm still gonna get temps above 220 on a slow uphill crawl even if I install a larger cooler?

I'm going to tackle this issue next and the 4x4 shop who is doing the work doesn't like the coolers with fans, mainly because fans can fail and a proper sized cooler is a better choice in their opinion. But I don't want to restrict air flow on these hot running 6.0 engines either. They are wanting to install a longer not so tall type cooler that's about as wide as the radiator.

Thoughts?

I'm still looking for the correct cooler to install.

[mtnrafter]

I've decided to go with an aux. trans. cooler instead of the larger pan... for now. Stopped by the mechanic today to discuss this topic. I noticed etbadger's Tru Cool, and I'm guessing others', was installed as a replacement instead of in series, so I asked if it is possible to install an aux. cooler in series given the limited amount of space our vans have in the nose. He's done several for loggers in Northern Idaho- pick ups mostly- and assured me it could be done- even the B&M units with auxiliary fans. I'm a bit skeptical but, if true, I might go this cooler/fan route. I'll find out tomorrow when I schedule a time to drop the van off.

Now, installing these things in series got me thinking about pressure drops on the return line, so I'll be sure to ask about this, too. Also, I'll ask about the reliability issue mentioned, above.

As to sourcing these parts, the shop will do that for me. Let's see what they find.

As to temps, I see 198-205 on long climbs in the Rockies. Once I saw 212 up Wolf Creek Pass. But on the way down it drops like a rock back to 160-170, then fluctuates up to 180, depending on outside temp, speed and load. In stop and go traffic, hot weather, the ScanGauge shows 191-198.

Thanks again for all the helpful responses.
Jay

[carringb]

Just be sure a "tube-and-fin" cooler does not get installed. Ford warns against using these, due to the pressure drop.

[Skywagon]

To clarify my previous post, I don't have an aux. cooler, just the stock setup.
Bill
PS: Ford says my temps are "well within factory tolerances".

[etbadger]

Originally Posted by Skywagon

On long grades or prolonged slow 4 wheeling, my transmission temps top out at about 230- 233 deg. It doesn't matter if it's Moab in Summer or Donner Pass in January. The ambient OAT doesn't seem to have anything to do with it. One would THINK it should, but it doesn't.
What it DOES do though, is to return to normal temps (180-185 deg. for mine) more quickly in the cooler OATs.
Bill

That would tend to make me think that the sensor tops out, or the radiator-stack fan kicks up speed, not that the transmission stops producing more heat than the cooler can dissipate...

The fan has a number of speeds that it can engage at though its viscous coupling, and kicks them up as a function of EOT, ECT, and Transmission temp. You can even put in a fan clutch with greater engagement at the slow-speeds (sold for pickups using plows, which block airflow to the radiator).

The reason we put the vents into out engine compartment was to allow the air the fan pushes to go somewhere, making it more effective at the lower speeds. Also helps the engine compartment cool off after getting toasty w/o popping the hood.

Even if the peak temperature the fluid reaches is the same, the less time it spends there, the better. Do a search online for 'transmission fluid temperature lifetime' and there are any number of graphs of service-life vs temperature. Getting to 230+ really really impacts this.

-e