What’s a good oil cooler to use on a F250. It’s a ’91, 7.3 IDI 2wd with a E40D and I tow up to 7000k max. Just did a tranny and debating on which cooler to use, any input appreciated.

 

bro there are so many brands and styles, it all depends on you, id go with a larger one but i have a C6 they tend to run hotter. Dont make it too big or the oil wont get up to good temps, go too small and too hot. anything like mine which is 12x16 iirc and itll do ya well. brands i cant help there, too many and different me being in canada.

 

I've got a hayden in mine, the biggest one they make but a need another one in line with it at 24,000gcw. But at 7k towing just one for 15 to 18k gcw would do just fine.

 

im using this one:
Automatic Transmission SuperCooler rated at 13,000 BTU 11"x7-1/2"x3/4"
with super results last summer (too much for winter/just right again with the plow on though.)

 

Thanks guys, was actually looking at the B&M products, 2nd choice was the OEM F250 super duty unit, huge cooler at 7x20" with OEM mounts.

 

I'm gonna need one this summer for the camper. Still doesn't have a cooler at all! Poor C6!


I hope I have enough room to put at least a big cooler (12x12 or 12x16) and if room put it's own electric fan on it with a toggle switch.

 

Ideally you want to get one that uses the flat stack construction instead of the serpentine pipe with fins. They have more surface area and will radiate more heat relative to their size. If you are retaining the OEM cooler in the rad, plumb the extra cooler after the OEM cooler, not before.

 

Why after? I was going to completly bypass the rad cooler, don't think it does anythi to cool- does it??

 

It does help some.

Pass it through the rad first to get rid of as much heat as possible before heading through the aux. cooler so it can finish it off nicely.

 

Makes good sense. Thanks!

 

Its a matter of preference depending on who you ask. My truck came with 2 coolers that were plumbed into the main cooler. One is a tube cooler and the other is a smaller flat stack cooler (flat stack cooler is always hotter to the touch). Everything was connected in series - which is supposed to be a no-no.

If you run 2 coolers, they are supposed to be in parallel to avoid line pressure drop although I never bothered to correct this on mine.

There are two trains of thought regarding the use of the OEM cooler in addition to an extra cooler.

1; you need to keep it in order to get the maximum cooling made possible by a direct fluid to water heat transfer. Direct fluid to air cooling will not be as effective as direct oil to water cooling.


or

2; you should avoid the OEM cooler because if the engine over heats or taxes out the cooling system, it will start to heat up your transmission instead of cooling it down. OEM coolers may also be clogged after many years.

The temperature of the rad is around 195F at the top. The temperature at the bottom is usually much lower and even in the summer, I noticed my rad is often cool to the touch at the lower tank.

This is the part where you have the transmission cooler coiled in. Thats fine when the truck is running light because transmission cooling is at its highest. However that lower part of the rad also acts like the reserve cooling capacity for the engine. So when you are hauling long and hard up a pass, that lower tank WILL heat up and its in this critical senario that you might *displace* the transmission cooling capacity as the engine coolant heats up.

From what I've heard, its not unusual for these trucks to sometimes run coolant temps over 210F, which would imply (I think) that the entire rad is very close to or perhaps even above the thermostat setting. Anything over 200 isn't going to kill a transmission, but its beyond the ideal range. How often a senario like this happens, I'm not sure.

So out of all that, it would be best to have your extra cooling after the OEM cooler, not before. If you know the rad and the cooler are in good contition, I see no issues with running the OEM cooler - but I bypassed mine...