I have a TH400 trans and am planning on a fluid change and see the finned aluminum covers and wondered if anyone can confirm if it really makes a difference in fluid temp? Is a trans cooler more efficient? Can you mix synthetic fluid with whatever happens to be in there now or is there is recommendation?
thanks
Steve

 

Do you race the car or have stall convertor. If not you are fine with the stock pan.

 

I cannot positively confirm an A to B comparison with and without both a finned pan and/or cooler…
But I can say that with a deep TCI finned aluminum pan AND a trans cooler, it’s very hard to get my temps above 150.

I never liked the idea of my trans fluid sitting next to 200 degree coolant in the radiator.
-peter

 

I seriously doubt you will see any difference in temp with an aluminum pan over stamped steel. About the only advantage of cast aluminum is most have a drain plug and are usually drilled abs tapped for a temp sending unit. With the thick pan rail flange, unless there is porosity in the casting they don’t leak.

The disadvantages:if your car sits low to the ground snd you hit something, cast aluminum pans don’t dent, they crack. They are also heavier, and more expensive. I can get factory deep pans and the required hardware from a used transmission warehouse for around 40-50 bucks, cheapest cast pan is around 125.

 

If both the synthetic and conventional fluid are rated for your T-400, then you can mix in any proportion.