Z28 Muscle

I have a '99 Z28 w/ a 3500 stall TCI converter and last summer my buddy and I installed a trans cooler because the tranny seemed to be getting hot when it was running for a while. The reason I think it's getting hot is because when it is locked up, and I give it a good amount of throttle (but not enough for it to downshift) the RPMs will jump up a couple hundred (like the converter is trying hard to stay locked but isn't able) then when I let off, the RPMs go back to their normal spot at that given speed. When the car/tranny hasn't been running long and I do the same thing, the RPMs steadily increase with the speed and the tranny stays locked without a problem.

Anyway, when the cooler was installed, I could run it all day and the tranny would stay cool, but recently the problem has returned, and the tranny seems to be getting hot again. Anyone know what the issue could be? There is nothing blocking air flow to the cooler...

Thanks in advance

Z28 Muscle

Anyone? Is the RPMs going up a little with the throttle when the tranny is locked up the transmission slipping or a bad clutch or do they just do that when they get hot? My friend says that it could have bad transmission fluid in it that starts to break down and get thin when it heats up, causing it to do a bad job of cooling the tranny. Any thoughts/input?

performabuilt

iTrader: (25)

A quick tilt in of the throttle will cause the PCM to unlock the converter even if its not enough for kickdown , When the car is cold under 140 engine temp it will not lockup at all normally ,

Z28 Muscle

It's not quite enough throttle to unlock the converter, because when I apply the same throttle say, after 15 minutes of driving, the RPM's don't go up any more than they do normally with speed. I have 3.73's, and normally cruise around 70-75 with the RPMs hovering about 2400-2500, could that be a bit too fast for the cooler to keep up with all the heat generated by the 3500 stall converter?