Problem Staying in Top Gear

[thebeavis]

Hey guys

my 4 runner is having problems staying in the top gear im guessing that is 4th for the 4 runners. I have read on the forum that the transmission shifts based upon the temperature, that in mind i always make sure the truck is warm before i go on the highway. Sometimes it shifts perfectly up through the gears and is perfect for highway driving but at times it will refuse to shift up into 4th or it will simply shift back into 3rd and wont upshift untill i slow way down and go up through the gears again. So i was wondering if it could be a faulty temp. sensor? since the tranny does not slip at all when shifting

Thanks
The Beavis

 

[fourwd1]

The auto won't go into O/D until the engine is warm. A flakey temp sensor might cause your problem, and I also would expect it to be logged to the ECM. Have you checked for CEL codes?

 

[fourwd1]

Knowing what year and engine might also help.

 

[nukefission]

I have this problem too but only when using cruise control. At highway speeds with cruise on, the anemic power of my truck causes it to downshift when going up hills. It won't however, automatically upshift back into OD once the road levels out. It will stay in 3rd with the RPM screaming at 4500 or whatever until I manually disable the cruise control - then it instantly shifts into OD and I can reengage the cruise in that gear. I have to repeat this process several times as the highways in my area are hilly.