Dropping out of Over drive. Please help.

2000 Chevy 3500 5.7 liter 108,000

Automatic Tranmission: 4L80E

I am driving 55 mph 2200 rpm, cool fall day straight road.

After about 10 minutes I drop out of Over drive and my rpm goes up 500.
(2700).

When I come to a light and start going all my shifts are hard and it will not go into OD.

If I stop turn the truck off and start again then OD works and very smooth shifts until 10 minutes later it drops out of OD again.

Hear is the weird parts:

Day two.
I rag on the truck. Full trottle all the time. Going up to 85 mph but if I start driving normal it will go into OD but after about 10 mintes boom, OD will not engauge.


Any idea?

1. Over drive worn out?
2. Tranmission over heating?
3. Computer freaking out?

Thanks.

I really could use some ideas on this one. I am totally lost.

Your having all kinds of problems aren't you? Sorry to hear that, i'm not even going try to give suggestions on this one. I have no idea what is going on with these R4700's. Thats the only part of my truck that has not given me problems.Oh and the cassette player has not given me any trouble either.

The 1 ton with the 80 auto tran was designed to drop out of OD if the engine sense a load condition. Make sense if you are towing 10,000 at 65 MPH.

Sensor is too senstive.

I will have to use a Hyper tech to fix this.