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question about overheating transmission

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Old 01-23-2011, 01:52 PM
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Default question about overheating transmission

my car already has a hayden cooler on it and it gets hot when the car is at idle like at long stop lights and in city driving it gets over 200degs and i was wondering when i got the tranny rebuilt the guy turned up the line pressure on the valve body and when the car was tuned the line pressure was turned up electronically so i was wondering if to much line pressure could get the tranny hot at an idle????

the pressure is up high enough right now that if i drop the car in reverse it will chirp the tires about 50% of the time so i was just seein what everyone thinks info would be great thanks
Old 01-23-2011, 05:34 PM
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What converter are you running? Whats all done to the trans? and are you still running threw the factory cooler then to the hayden?
Old 01-23-2011, 10:16 PM
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Originally Posted by khoward8509
the pressure is up high enough right now that if i drop the car in reverse it will chirp the tires about 50% of the time so i was just seein what everyone thinks info would be great thanks
What does it idle at when it chirps going into reverse?
Line pressure high enough to chirp reverse can cause it to run hot at idle.
High idle speed will cause it to run hot and chirp reverse.

People need to learn that these transmissions don't need over 240 PSI at WOT, and thats even on the high side. These need to be tuned only for higher shift pressure and higher tcc apply pressure when needed. The constant pressure table should never be tuned much let alone high enough to chirp reverse.
Old 01-25-2011, 11:05 AM
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thats why i was wondering if it was something to do with the line pressure or if it is with the high idle or both..

the car idles at about a 1000 rpm i am pulling the computer back out and i am gonna get it retuned to idle at about 850 and i wanted the line pressure backed off. I am not sure what kind of pressure the tranny is putting out right now but it over heats at an idle when you go down the road it is fine..

The conver is all stock the tranny is'nt much over stock the fluid runs through just the hayden and not the stock and hayden is in front of the radiator where it belongs.

so do you guys think i should drop the idle and the line pressure??
Old 01-25-2011, 11:45 AM
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The force motor values should be set to stock. Is there any reason you need it to idle at 850?
Old 01-25-2011, 02:07 PM
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1000 just seems high to me doenst seem like it needs to be that high... what exactly is the force motor
Old 01-25-2011, 02:35 PM
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The force motor table in a tuning program changes the line pressure constant. A lot of people use this trying to make shifts more firm, fix lock up problems, etc. But it's a constant meaning when you use it to increase line pressure, it increases it all the time. Idle, reverse, low load, everywhere.

No one seems to realize you can increase just shift pressure on the upshift pressure modifier table. And base shift pressure table.

If the constant pressure table needs to be messed with, it's either to fix a weak transmission, inexperienced tuning, etc.

And about the idle, yea 1000 is high considering stock is 550 hot. Thats why I asked.
Old 01-27-2011, 11:29 AM
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the motor just has a mild cam in it so i was figuring right around 850.. im putting the intake back on it this weekend and i am gonna pull the computer out and send it out in a few weeks hopefully it fixes the problem thanks alot




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