Shifts in and out of OD at highway speeds?any ideas

[Sandhappy3.0]

I have a 1999 RangerXLT 3.0L Flex Fuel 4x4, it is shifting in and out of OD at highway speeds. I have replaced the Throttle Position Sensor thinking that could be it but it was no help. If anyone has had this problem or knows something about this problem I would love to hear any ideas or solutions.

 

[Bruce]

Put a scanner on it and check for codes.....could be possibly a bad speed sensor.

 

[AllanD]

WHEN is it shifting in and out of od?

what throttle demand?

What speed?

Upgrades?

AD

 

[Sandhappy3.0]

shifting in and out at 70 mph and higher and it happens only when i get on the highway with alot of throttle it seems if i just get on it easy it wont happen untill i have to get on it hard the only upgrades are a cold air intake kit 31x10.5 tires and some exhaust upgrades nothing major

 

[Redneck1912]

Its suppose to do that so the trans doesn't overheat.