Drive in OD, but does not go into OD

[1Byounkin]

1991 explorer 4X4. The transmission has been rebuilt about a year ago. Ever since then only runs in the gear before overdrive. I drove in 'D' and then shift into [D] when the truck should go into Overdrive, but no change. Yes it will take off in [D] and the other gears without overdrive kicking in. What is a simple fix? I have received info on how to change the bands, but that's more than what I want to tear into.

 

[Verno]

Could be either your modulator or the linkeage. Have you read up on these in the tranny section?

 

[mgmgmg]

I had the same problem it was the mass air flow... next to the air filter..... replaced it OD work.. I know what you mean every gear works just wont shift into od. Just buy a 30$ code scanner that how i foound the fix....

 

[MrShorty]

to make sure I understand: in the OD position, it is driving like a 3 speed transmission? Is the torque converter locking up in 3rd gear?

3-4 shift and TCC lockup are electronically controlled by the PCM. In a situation where the transmission is operating fine 1st through 3rd, I'd first determine if the computer is commanding the upshift or not. I know I've posted more detail in chasing the electrical side of the 3-4 shift. 1st step would usually be to pull codes from the computer.

If the TCC is not locking as well, the first thing I might do would be to check the plugs on the side of the transmission to make sure they are plugged in. It wouldn't be the first time someone installed an A4LD and forgot to plug the solenoid connector in.

 

[1Byounkin]

can I still get codes even when the check engine lights is not on. If I unplug the Mass air flow and run it would there be change? Just to know if that is bad. I'll check for unhooked wires. That sounds more like it than doing adjustments. The transmission has never locked in to OD since the transmission was rebuilt.

I do have a code checker.

 

[1Byounkin]

So adjustment would work

So if I adjust the bands as found on this page http://www.explorerforum.com/forums/showthread.php?t=158160 Would this finally get me OD. I do notice a little change when the rpms are at 2800 at 65mph, than the rpms down to 2600 (hear the tone in the motor change on level ground) I'm new at this on adjusting the bands.

 

[MrShorty]

can I still get codes even when the check engine lights is not on

Yes. If the computer has nothing to report, you will get pass (11) codes.