Overdrive Off = Transmission Temp Drop

[mtbtim]

Thanks for getting back!
I have read that a temp sensor of some kind will cause the lack of o-drive problem. Any info about this would help for sure. What sensor, location, and will it help?

The temp sensor for the trans is on the passenger side of the trans from what I remember. I've never replaced one though.

 

[Bad Luck]

Thanks for getting back!
I have read that a temp sensor of some kind will cause the lack of o-drive problem. Any info about this would help for sure. What sensor, location, and will it help?

Do you have a way to see what the coolant temperature reading from the engine control module is? Does your instrument cluster temperature gauge work?

It could also be a valve body issue or a mechanical problem with the transmission. What did your transmission fluid look like?

 

[gamefreakgc]

Thanks for getting back!
I have read that a temp sensor of some kind will cause the lack of o-drive problem. Any info about this would help for sure. What sensor, location, and will it help?

If yours is a 96-98 then the temperature sensor is pretty basic and I doubt it is the issue. If you have a 99+ then you can read it with an OBD-II bluetooth module + phone app or wired handheld. I do not know of any threshold that will prevent shifting.

Are you sure it's overdrive (4th gear) and not torque converter lockup? If it's overdrive that will not shift, then clicking the button on the gear shifter will do absolutely nothing. If it's the torque converter lockup then you'll have it downshift but not lock up. If it is indeed 4th gear that is toast you could try swapping out the valve bodies on the transmission as that is not a terribly difficult job. Could pickup a used unit from a junkyard. Otherwise you're in for a new transmission.

If it's the torque converter it is not really any better. Sure you can keep the transmission but the amount of work and labor to get to the torque converter is the exact same as replacing the transmission itself.