I have a 4l60e with shift kit, new pump, new clutches and a lot of new stuff inside it, had it built before my ls1 swap into my Vette c3, has mild ported heads and mild cam.

i just installed a stand alone controller for the trans, the msd tcm, good little unit, has safety's for the trans too.

it shows a readout of the fluid temp, which I'm guessing uses the same temperature sensor as the hp tuners, and as it is in the middle of the trans it absorbs heat from all the metal (and heat soak) around it rather than than constantly moving fluid in the pan.

if I drive long enough, the trans fluid temp hits 250f, that's the highest I've seen, and seemed pretty steady. Even at highway speeds with lockup. I don't doubt that on a hot day (mind you it's winter here in Australia, gets another 50f hotter than the past few days) it would go higher.

The msd tcm has a safety at 270f that locks up all gears above 2% throttle or something. Which does seem high, all readings seem high

i am monitoring all this as I have a 3000stall going in, and also a plate style cooler, and getting worried about having high temps on a shift kitted new 4l60e, imagine what a higher stall verter will do.

just then I went for a 45minute drive, trans got up to 215 according to msd screen, jumped out with a laser thermometer thing and scanned the bottom of the pan while the car is still idling, I was getting 100-120f from the pan.

has anyone else been in the same situation? Giant difference, what sort of "scale" do you use when you have hp tuners temp (or similar), like do you pull over and let the car rest if it hits 280f? As the actual fluid would only be about 200f?


And any tips to keep the trans cool besides another cooler? I was thinking of putting a bit of a heat shield between the pan and both exhausts either side (there is a bit of clearance, so it wouldn't really effect it at cruising, but hey, it's free and will help at a stop a little)

i also think that my new radiator's trans cooler isn't very efficient, I think it actually looks like a "drum" or "cylinder sitting in the radiator as opposed to a spiral or something with a lot of surface area, my new plate style cooler will be going in a front grill of the Vette and be "sealed", like a ram air cooler, any air at all HAS to pass through the cooler at that point, so cruising will be very efficient I believe,

 

Built tranny needs external trans cooler. I'm convinced its "almost" impossible to over-cool an auto.. I usually go with a plate style thats the width of the radiator and about 1/3 to 1/2 the height of the radiator.

I like to see 180 to 190 on a 70+ degree day.

I usually use a canton thermostat to bypass the cooler when the fluid is cold.

Just .002 cents worth..