I have a 04 RAM 4.7L with the 5 speed automatic with 1200 miles on it.

Is there any reason to believe that the transmission has to warm up (slightly) in real cold whether in order to shift into overdrive (or lock the torque converter)?

The reason I ask is yesterday I got on the highway a couple miles from my house and I accelerated to 70 mph. I was about to set the cruise when I noticed the RPMS were at 2500. After a 5-10 seconds it didn't shift up...so I pressed the tow/haul button to force a down shift. This worked and the engine reved to 3000+ then I turned off the tow/haul button and the transmission shifted right down to 2000. (This was the RPM I expected to see earlier.) After that I tried it again a few mins later and it shifted quickly down to 2000 on any accelerations. I never noticed the slower shifting before in fact if anything it seems to shift slightly too soon sometimes.

Any thoughts or similar experiences?

 

I'm sure the pcm holds it from lock up until the engine warms suffiently to run smoothly and not produce excess emmissions. GM's work that way.

 

Hi Matt.

My '95 Ram 2500 with the four-speed auto used to do this as well. I just figured it was avoiding engine lugging until the engine was ready for it. In fact, I used to watch the temperature needle and at a constant ~40 MPH, the transmission would lock up just as the temperature passed the first tick.

Probably a common trick and nothing to worry about.

- Dave

 

Thanks

 

The 5 speed in my 04 hemi does the same thing. The owners manual says it is supposed to stay out of OD until it warms up.

 

I have a 96 auto transmittion and it does the same thing no matter what. Everything could be hot and it still won't shift. I think it might be something wromh w/ torchconverter