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Re: TRANSMISSION OVERHEATING!!
Posted: Fri Aug 26, 2011 5:13 am
by Slinky
daguse is right thats what i did
Re: TRANSMISSION OVERHEATING!!
Posted: Fri Aug 26, 2011 5:19 am
by Slinky
could my trans passage in my rad being clogged be causing this?
Re: TRANSMISSION OVERHEATING!!
Posted: Fri Aug 26, 2011 8:33 am
by 3X00-Modified
Possibly, but all you need to do to test that is pull one of the lines thats going into the trans to see if the fluid is flowing through that.
Also when you do a cooler install that way you end up with a trans heater/cooler... if you think about it they ran the trans oil through the coolant since the coolant heats up quicker to transfer heat to the trans and warm that up as well but also control the temp at the same time. So unless you put the external cooler inline AFTER the radiator cooler then you are not helping much, it will always be the temp of the engine. IIRC the fluid flows back into the trans in the line thats going in horizontally, the vertical one that points down I believe is the pressure/feed port to the cooler.
Re: TRANSMISSION OVERHEATING!!
Posted: Fri Aug 26, 2011 6:36 pm
by Slinky
i checked the vac lines and there was a T fitting with and open end DERRR!
I plugged it and did some highway driving and the trans temp stayed right with my engine oil temp,
JON you are my hero!
Re: TRANSMISSION OVERHEATING!!
Posted: Fri Aug 26, 2011 8:01 pm
by Chad91GTZ
Combustion engine is just an air pump, chances are if its not electrical, you should start with vaccum.
Re: TRANSMISSION OVERHEATING!!
Posted: Fri Aug 26, 2011 10:22 pm
by 3X00-Modified
Glad you found the issue

Re: TRANSMISSION OVERHEATING!!
Posted: Mon Sep 05, 2011 11:20 am
by Slinky
Ok so the trans is still heating up GRRRRR
It seems like id i completly baby it i can drive around 20mins before it starts to heat up, but when i baby it it goes up at the same rate as my engine temp which is expected, only when i get around 200deg my engine temp stops going up and the trans temp keeps going, and it seems like as soon as i beat on it about 3k the temp will shoot up and not come back down,
someone tell me wtf is going on, i got fluid flowing through the rad through an external cooler and both have dual fans running nonstop, and the trans temp is still overheating..
Re: TRANSMISSION OVERHEATING!!
Posted: Mon Sep 05, 2011 11:26 am
by DTMAce
Are we sure the temp gauge unit you have installed is working or calibrated properly? Have you felt the transmission's casing to see if it was really hot when this occurs? Like the bottom of the pan or even the outgoing/return line where the metal is? Just might be nothing wrong and the gauge is reporting it being hotter than it actually is.... Usually a hot transmission will start slipping like a bitch, and you can even sometimes see vapor come from the fill tube if you pull the stick out. You can feel the temp of the stick, to see if its way too hot as well. Borrow a heat measuring gun and check it that way maybe. Something to think about.
Re: TRANSMISSION OVERHEATING!!
Posted: Mon Sep 05, 2011 11:33 am
by Slinky
my temp sensor is in my return line, ill try to get ahold of a temp gun
Re: TRANSMISSION OVERHEATING!!
Posted: Mon Mar 26, 2012 5:34 pm
by Slinky
ok so dead thread revival..
I had the trans rebuilt professionally after the first time where it was effed up, it is still over heating and will not seem to cool down..
I have the fluid running through the normal rad cooler, than through an external cooler, than back into the trans, and i removed the plastic in from of the rad behind the bumper to help air flow, and i also have a ZZP aluminum heat sink pan and i have dual fans 600cfm each running on the rad to help but it still overheats if i sit and idle for to long or stomp on the gas at all.. the last time i tried to drive it it was ok and went up with my engine oil temps but when i pushed it the trans went up to 240deg and it looked like it was not going to stop so i shut it off..
heres some pix of my setup..
dual 600cfm derale slim fans
motor oil on the top and trans fluid on the bottom, also gaped from the rad

Re: TRANSMISSION OVERHEATING!!
Posted: Tue Mar 27, 2012 8:20 am
by 3X00-Modified
I don't know what to tell you other than check your trans pressure to ensure there still isn't something wrong with the pump/pressure regulator setup... It honestly sounds like you have the pressure cranked up and it's just generating heat like crazy... Also why an oil cooler thats larger than your trans cooler?? The trans oil needs to stay cooler more so than the engine oil believe it or not.
Re: TRANSMISSION OVERHEATING!!
Posted: Tue Mar 27, 2012 12:22 pm
by Slinky
How would i go about checking the trans fluid pressure?
And i got that dual cooler for rather cheap, i would like to keep the dual cooler idea but i cant find another bigger on in my price range, derale makes another dual cooler thats 8 pass X 8 pass and is a good deal thicker but is smaller in height and width, i just dont want to waster another $75 for a diff cooler if it wont work any better..
Here it is,
http://www.jegs.com/i/Derale/259/15301/10002/-1
In theory i shouldnt even need another external cooler because alot of berettas only have the one in the rad which is why i cant understand why it wont stay cool..
Re: TRANSMISSION OVERHEATING!!
Posted: Tue Mar 27, 2012 2:32 pm
by 3X00-Modified
There is a port on the top of the trans that is just a brass NPT plug, if you get a trans pressure gauge you can check the pressure there.
in P, R, N @1250RPM
It should be 74-95PSI with 18in vac on the modulator
In OD, D, L, @1250RPM
it should be 74-95PSI with 18in vac on the modulator
We don't have a 1 position on our selector but that states 158-170 with 18in vav on the modulator.
Now with the modulator unplugged from vac it should read this
P,R,N @1250rpm
255-315
OD, D, L @1250rpm
165-205
Re: TRANSMISSION OVERHEATING!!
Posted: Tue Mar 27, 2012 5:15 pm
by Slinky
could the amount of vac going to the modulator or the modulator have anything to do with this overheating?
Re: TRANSMISSION OVERHEATING!!
Posted: Wed Mar 28, 2012 9:03 am
by 3X00-Modified
Yes... not enough vac and the modulator will keep the trans at high pressure which will cause heat, or the wrong modulator or the right one adjusted way to tight will do the same thing.