TRANSMISSION OVERHEATING!!

[Slinky]

could i run vac straight from the plenum or somewhere safely to the modulator with vac hose?
To much vac wont hurt it?
If so ill just try doing that and have an independent vac line to the trans

[3X00-Modified]

What do you currently have for a vac line going to the modulator?

Factory line leaves the corner of a 3100 plenum and goes to a T to the modulator immediately, Engine Vac will only hit 20-25in max typically and no that wont damage anything, After the modulator the rest of the vac lines are fed from there going to the canister as well, there is a one way valve between the modulator line and canister so the canister always has vac even in a wot condition; where the modulator will see the drop from vac to ambient pressure which increases the trans pressure.

Now if you have this plumbed wrong or improperly which is limiting the vac to that modulator then you are overwhelming your pump with the request for max pressure therefore creating your own heat issue.

[Slinky]

I hooked the lines up properly, they were alittle differant than how you said and it still went to 220deg and was still climbing, where would i get something to check the pressure?

[DTMAce]

I said it before, but still don't recall an answer. Are you sure its actually getting that hot? I still wonder if the temp you are seeing is accurate.

[3X00-Modified]

Do you have a tuning software setup? Or do you have all this done and no tuning software? because with a HPTuner or DHP you can monitor the trans temp from the sensor in the pan. Which is one reason why I don't understand the need for an external gauge.

You need to buy a 0-400 PSI pressure gauge... They sell them on Amazon and I'm sure you could walk into a auto store and order one from them, but they are only like $40 on amazon.

0-300 will suffice since you shouldn't see much over 300 PSI anyways.

http://www.amazon.com/Advanced-ATD-5550 ... B000OUZBZ0

[Slinky]

i have a dhp tuner but have no knowledge of how to use it ect, tuning is something i have no clue about, and i am also trying to work out some wiring issues with my obd2 swap at the moment

and DTM i did have it checked once with an infared temp gauge, and i ordered one last week and i am waiting for it to come it to be completly sure, my gauges matched the infared gauge in the past..

[3X00-Modified]

Scan your computer while its running and get the transmission temp pid to show up, thats your verification.

[99GaGT3X00]

0-300 will suffice since you shouldn't see much over 300 PSI anyways.

shouldn't be that high. the max pressure on my 4t45 is 96psi unless the 4t60 is radically different.

[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
255-315PSI

OD, D, L @1250rpm
165-205PSI

[99GaGT3X00]

damn unplugged that's some pressure. and i thought mine was high..

[Slinky]

So i found out the guy who rebuilt my trans didnt put a new modulator on, so i got a dual stripe adjustable one to see if it helps my over heating issue..

So what is the best way to set or adjust the modulator to have good firm shifts but have the trans not overheat?
like how many turns and turns in or out ect?

I didnt order my trans pressure gauge yet, i wanted to see if this fixes it first..

[Slinky]

i put a new modulator on, when my trans temp was about to 120*F and my engine oil was at 200*f i used an infrared temp gauge to check the lines while it was idling, it said:
Line coming out 200*F
Line going back 180*F

Could my temp sensor just be getting hot from the engine or exhaust heat and staying hot?
Im rather sure my temp sensor is within a few degrees

[3X00-Modified]

I would be checking the temp sensor through the ECU and NOT with an infrared gun... Thats giving you the hose temp which could easily be absorbing heat from elsewhere.

My ecu reads a max of 170 while driving around in a town enviornment, not highway locked up... in that case I get around 160 peak.