Hello all,

This is my first post but I follow this forum since a year ago.
I have a 98 Grand Cherokee Laredo, 4.0 and 42RE transmission, and recently it is not going overdrive anymore but TC lock up is fine and pressing overdrive button (OD off, button light on) makes it to lock earlier, other gears are shifting fine (sometimes it does a single clunk noise when shifting to reverse). Also, it has no errors in OBD.
It has 126k km (78k miles more less) only and I'm the second owner.

Do you have any idea which could help me before going to auto zone?

Sorry for bad english, I'm from Brazil.

Thanks

 

Welcome to the forum.

The OD is actuated by a solenoid within the transmission.

It is possible the solenoid has failed, or the wiring that powers the solenoid has failed.

 

Is there any way I could check if the wires are ok?? Maybe a wiring diagram.