# transmission O/D off trans temp light



## belcourt31

I have a 99 dodge ram 1500 v8 5.9L 4x4 with a 46re transmission. I rebuilt the transmission 2 years ago and has ran great since recently. the truck will drive great until about 15 min down the road, when the truck is warmed up and the overdrive will turn off and shortly after that the trans temp light will come on and it stays in limp mode until its cooled down...ive replaced the radiator because the transmission cooler is in the radiator. i replaced the wiring harness on the valve body 3 times and I have replaced the engine coolant temp sensor, and i have removed the checkball in the transmission cooling line and anfter i put everything back together it still turns the overdrive off and is still acting like the transmission is overheating and the transtemp light comes on shortly after the overdrive turns off


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## Wrench97

Do you have access to a scan tool that will read the trans temp?

Have you tried changing the Governor Pressure Sensor(in those older models had the temp sensor built into the GPS)?


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## belcourt31

i took it to a shop they guy had a snap-on machine he told me the temp was around 208 i believe he said, but he said it wasnt anything to be too worried about. it has to be something electrical because when i first start to drive it it runs great mechanically. and yes when i repaced the wiring harness on the valve body it came with a new Governor pressure solenoid


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## Wrench97

Was the overheat light off or on at the time?

If it was on and the temp was that low then the ECM/PCM may need a reflash.


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## belcourt31

i wasnt with him when he put it on his machine, i assume it was on at the time, what is a reflash?


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## Wrench97

Reinstalling the firmware(software) in the control module, it takes special equipment either a dealer or most areas have a tech that travels around and does it for various shops.


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## belcourt31

Any idea about how much it will cost


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## Wrench97

It varies by the area and who you find to do it dealers $200-$250, if you find a local tech(ask around at body shops they use the mobile techs for resetting SRS controls and other accident damage, since they'll have no skin in the game for a trans they may give you a contact number) The mobile tech I've used gets anywhere from $75 to $150 depending on how long it takes and how much he has invested in connection fees to the source(Dodge in this case)


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## belcourt31

I'll look into it, thank you


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## Panther063

Odd, I thought default limp mode was locked in overdrive, because of the direct drive through the trans, or at least that was how it was explained to me when I had an auto trans go bad on me.


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## kendallt

only high gear is direct, any gear that increases or decreases speed at the output shaft goes through the planetary gear sets on autos or the counter shaft on manuals

Advice I got from some Dodge freak friends when I was looking at a ram 1500 was to either get a manual (my preferred) or to install an aftermarket cooler and bypass the radiator cooler with the overdrive automatics. They also stated that the temp sensors on certain years were off by as much as 60 degrees when checked with a regular thermometer


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