Engine/Transmission (1998.5 - 2002) funky OD shift in Cold Weather

[GaryMoore]

Hi Guys, long time no talk to.

I have been having problems with my truck shifting into OD since the mercury has dipped below 0 degrees. The first OD shift when the truck is cold will not happen for 5 or 10 minutes at highway speed. After the first shift the truck seems normal again. I had read in other posts that this could be normal. True or false?

thanks... gary moore

 

[DLausche]

I think it will shift into OD/4th when it is cold but the PCM will not lock the torque converter until it warms up to a certain temp. This is what mine does when it is cold in the morning. Could this be what you are experiencing? Not sure if the temp is engine or trans temp. Anyone else know a bit more about this?



-Deon

 

[GaryMoore]

How do I tell if the torque converter is locked or not? I get my last shift at 45 - 50 when the transmission is warm now I do not get that last shift for 5 - 10 minutes after the truck is running down the road. I know that when I was having problems with the TQ locking and unlocking (fixed it with a DTR filter) it felt like a OD shift.

..... gary

 

[FourBarR]

there is a thermister in the transmission that prevents shift into od until temps in trans. are up to preset. normal. hope this helps.

 

[B.G. Smith]

How do I tell if the torque converter is locked or not? I get my last shift at 45 - 50 when the transmission is warm now I do not get that last shift for 5 - 10 minutes after the truck is running down the road. I know that when I was having problems with the TQ locking and unlocking (fixed it with a DTR filter) it felt like a OD shift.

..... gary

The torque converter won't lock up in 3rd gear unless the OD button has been depressed (turned off). The transmission won't shift into overdrive when the transmission fluid is below 50 deg. F or above 250 deg. F or the battery temp is below 5 deg. F bg

 

[GaryMoore]

Man, where do you guys get this information.

Thanks. . gary

 

[bmoeller]

The torque converter won't lock up in 3rd gear unless the OD button has been depressed (turned off).

Mine will lock te tc clutch without the O/D being locked out, even the stocker. Maybe the later ones are different.

The transmission won't shift into overdrive when the transmission fluid is below 50 deg. F or above 250 deg. F or the battery temp is below 5 deg. F

Yep.





Say Gary, have you been watching the thread on the IL TDR get together on the 17th, or are you still in the area? As far as I know it is still on. I plan on being there. http://tdr1.com/forums/showthread.php?t=133808