I have a 2001 QC 4X4 4.7ltr when the weather get cooler say below 10C or 50F my tranny will not go into Overdrive until it warms up.

Is this a safety feature or do I have a issue not an issue in the summer it works fine.

 

Perfectly normal operation.

 

Any answers or is that true?

 

Bwdakrt answered your question.

He's absolutely 100% correct.

 

no not normal. your internal fluid filter is clogged. i have had this happen in cold weather. on older trans like the old 727. would not go into rev. cause rev needs a lot more oil. ill bet the OD is the same way. do this change fluid and filter. here is a new thing. an external filter, go to auto zone get 2210 magna-fine filter. should be 3/8 tube, in the line returning to the trans, the line on the left side at the rear is the return line. use high pressure hose. the filter goes inline with the coolant return line. you will need to cut some tubing. i like this cause i think you will need fewer pan, internal filter changes.

 

WRONG. Dont care if sarcasm or not, I dont take wrong info well. The Transmission overdrive is controlled by electronics and the electronics will not allow it till above a certain temp (120?) if the fluid goes below a certain temp (70?) It is because the fluid will be to viscus and thick and will not flow correctly, and if it doesnt flow right then you could burn out your overdrive. The old TF 727 has no real relevance to today's transmissions. Sure maybe back in the RH days, but the RE and RFE, totally different.

 

I'll back Dakota Greg with this, he's right. The transmission won't shift into overdrive until it warms up and that is by design.

Many newer cars do this as well.

 

the owners manual says it will not allow it in to overdrive until it reaches operating temp. and the shift timing is also different when it's cold

 

So I'm not trying to thread jack but I have a somewhat related question. If the automatic transmission won't shift into o.d. untill its at a certain temp should I avoid putting my manual trans into overdrive before the truck is at a certain temp? Or is the manual trans able to handle o.d. right away

 

Mine does this as well won't go below like 2000 on highway till its warm.