Trans cooler mounting

I have a derale 13613 stacked plate style transcooler suppose to be good for 20500 lb gvw. Is there any effective difference with inlet/outlet orentation? Right now it is running in front of radiator, with both ports facing downeard toward the ground and have an electric fan set as a pusher on full time on it. As of now trans temp gauge at the inlet reads about 190 to 200 on highway on a 95 degree day in lockup on a 2004r. Seems alittle hot to me. Not sure if it how it is mounted or if unit might be too small


What's An Intercooler
Staff member
Imop that's a small cooler. There are much better units. However I'm not sure how that cooler is setup internally but with both ports down you won't get full fluid coverage on the cooler it needs to have ports sideways or cooler flat. If you want you can run the fluid through the radiator first then the cooler that will help some. But if you only run a external you need a big unit

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I was thinking it might be a hair small. I will try turning it so that the ports face sideways towards the passenger side for the time being to see if there is any improvement till i can save up some for a larger unit . May go for the B&M 70274
Yes . Exactly how i will be mounting it. It will be todays project. And since it will be 91 degrees here today be a good test day once finished. Thank you for the help
at the cooler. for now. i do have an aluminum hughes pan that needs to be installed. so i plan to have a proper bung welded to it before installing.
i remounted the cooler today with inlet/outlet facing passenger side of car and put the inlet at the bottom . also redid the mounts to allow fan to be mounted on the back side to work as a puller instead of pusher. still have to to take it for a decent drive to see how it does.


What's An Intercooler
Staff member
This is the one I have

Trans runs nice and cool. I just started running the fan on 24.7 when the engine is on. It was hooked to the thermal switch but I like to try and keep it cooler before it warms up that hot. I think the switch is a 175deg.

Derale also makes some nice coolers.

If I was to do it again I would get this one

But again my current one works perfect and its sized just right for Arizona temps

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I was eyeing up the B&M 70274. good for 29,000 btu's without a fan.

and then finding an correct size and cfm fan to mount on it.i think between 1000-1200 cfm should be suffecient. The Derale unit would have been sweet if it had npt inlets since i already made brand new hardlines from trans to the cooler. see it is rated at 67,000 btu's even though it is smaller then the B&M i am looking at. i am guessing it is cause of the fan.
i am also wondering if my gearing has anything to do with it. i am running 4.10 gear in the rear. 1st to 2nd is around12-15mph send to third is around 30-35 and 4th gear no earlier then around 45 mph. it really stretches 3rd gear. not sure if that is normal. these are also at about 1/4-1/2 throttle cruising around town or going on highway.


Staff member
What rpms are you seeing, just normal cruising at say under 40mph?
If it's singing pretty good, I would suspect that and the small trans cooler could affect trans temps.
Definitely upgrade the trans cooler if you don't want to run it in series with a radiator trans cooler.

These engines, with their unique hp and torque curves, don't need a lot of rear gear. Is your car an "86/"87 LC2 powered 3.8L turbo v6 Buick? Typically at most, you'll see someone running a 3.73 rear gear, with the majority sticking with the 3.42's. You can go really quick with the 3.42's fwiw. Really quick and fast...
The 200 trans' gear ratios, combined with the 3.42 gears, take excellent advantage of the 3.8 turbo V6's hp and torque curves.

Just thinking out loud.