Transmission Oil Cooler Recommendations

[conoco]

Any recommendations on the size of transmission cooler you would want for a 72 k2500 (TH350) I use it a lot going up into the mountains and I see a lot on the various sites. Rectangular, square, long tubes. I didn't know if there was a rating that works best or a size. Any help with someone running one of these would be great.

[Stocker]

Can't help you with the particulars -- I'm sure others will -- but I wanted to pass along some information that might be helpful.

I looked into these years ago, just never bought one. Somewhere I read that transmissions like for the fluid to be at a certain operating temperature. It's possible to cool the fluid too much, for instance if you plumb it through your existing radiator first and then through the auxiliary cooler before returning to the transmission. It was recommended to have the fluid go through the auxiliary cooler first, then through your existing radiator's cooler. The idea was the coolant would help bring the trans fluid up to temp if it was too cool, and at the same time, it would not cause the fluid to rise above recommended temps.

[Andy4639]

GM recommends to keep automatic's below 200 * anything over 200 start's breaking down the fluid. I run mine as mentioned aux cooler then stock.

[LS short box]

I haven't done any towing but I use the biggest "flat plate" cooler I can fit in front of the radiator. B&M is what I'm currently using. Some would recommend running the trans fluid thru the radiator cooler also to manage the fluid temp.

[BCOWANWHEELS]

Stock, cant beat it

[3767]

Check into swapping out the stock pan for a finned 1 with a temp port. U need to know how hot it’s getting before u add a cooler. Also change from regular fluid to synthetic. They are made to handle the heat better.U may not even need an auxiliary cooler once u know just how it’s running. Once u see how hot it’s actually getting then u can get a plate style with or without its own fan or go to an aluminum tube style with fins. These will mount along the frame. They are made to work with the stock radiator or they can b used stand alone.

[BCOWANWHEELS]

with a deep pan it will hit the x member a little so it will need modded

[Andy4639]

Living in the south I haven't ever been worried about it running to cool.
If your up north then yea you may need to worry about it in the winter.
If you pull a trailer with it a lot it's a good idea but for just driving the radiator cooler should be just fine. Just remember the water temp is 180* are so, so you have a small margin of cooling to keep the recommended 200* for the trans temp.

175 degrees

The ideal operating temperature of transmission fluid is 175 degrees. Overheating occurs after the temperature surpasses 200 degrees, and the failure rate doubles for every additional 20 degree increase after that.

[conoco]

Thanks everyone. I think I will keep it stock and add a deeper pan. I'm in alaska and it only summer for 3 months. Really 2 lol. I was worried about all the mountain driving i put this truck through heading up to my house. It runs great, no problems, I just didn't want to start a problem if I could have just added something to help it. I will do the above to see what the temp is running at now. Thanks for all the thoughts. Appreciate it.