So I added a cooler to the Pontiac Montana. 4T65E. Its all metal pipe except for a small section in the middle. What I did was cut the hose and spliced in the cooler there. I thought it was 5/16" hose because the transmission hose I had left over from another project was the same O/D. Could not find any markings. Well, it must be 3/8" because now it pours out of the fittings like it was made to do that. Should I up grade to 3/8" stuff all the way, which will invalidate all the fittings I just bought, and the hose, or just buy 3/8" to 5/16" adapter.
Transmission Cooler.
- Thread starter Colt45ws
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I don't understand what you mean by "now it just pours out of the fittings like it was made to do that"....are you saying it's leaking? I remember reading the flow rates of the 3 common ATF hose sizes (5/16", 11/32" and 3/8" inner diameters) and although I can't remember them I was surprised at how big the difference was. I would try to use the correct size hose but would go larger if I couldn't find it.
Yes, it is leaking.
Ill adapt them for now, and then later go back through with the correct fittings and hoses. Itll just have to wait because Im $30 into this with just fittings. I had to make adapters because they didnt have any, they were even out of 3/8 barb to 3/8 if I wanted to squeeze my 5/16" hose over that.
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When this transmission is in high, and the lockup is on the factory cooler is way more than adequate..
I have been towing a 5,000 lb low profile boat with a APV for the last 250K miles, 4 days a week - remarkably the fluid never discolors ever. A infrared temp gun never reveals temps above 220 degrees, usually around 200.
What are you towing that requires a cooler??? I always suspected that a tall flat fronted travel trailer might pull hard enough to knock the lockup off a lot... that will send transmission temperature straight up!!
I have been towing a 5,000 lb low profile boat with a APV for the last 250K miles, 4 days a week - remarkably the fluid never discolors ever. A infrared temp gun never reveals temps above 220 degrees, usually around 200.
What are you towing that requires a cooler??? I always suspected that a tall flat fronted travel trailer might pull hard enough to knock the lockup off a lot... that will send transmission temperature straight up!!
200 is a little hot for me. This isnt a large cooler, so itll knock it down 5-10 degrees and Ill be happy. I plumbed it after the factory cooler so itll actually be doing something.
If it leaks with 5/16, it will leak more with the larger 3/8 line.
Got it redone properly with 3/8".
I went and took it for a good hard drive. As I was pulling into the driveway I used my SG-I to ping the computer for transmission temperature. Had to do the decoding manually, but I got 176F when coolant was 197F. Seems to work pretty well. It is positioned right in the lower bumper openings, so it gets plenty of airflow when its moving.
I went and took it for a good hard drive. As I was pulling into the driveway I used my SG-I to ping the computer for transmission temperature. Had to do the decoding manually, but I got 176F when coolant was 197F. Seems to work pretty well. It is positioned right in the lower bumper openings, so it gets plenty of airflow when its moving.
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