92 explorer no forward in OD but fine in D

[power67]

Hello all,
Thanks for all the great info in this forum. I have a 92 explorer that is giving me some trouble. I just got it from someone and she said that she never had tranny problems with it. It was slipping in forward and reverve quite badly. I dropped the pan for inspection and a fluid change. There was the normal amount of clutch matter buildup on the bottom of the pan and the fluid was dark but not burnt and had no matalics in it.
After the fluid change and topping off of fluid, I have great reverse. If I shift the selector into Overdrive, the tranny engages but does not have the ability to move forward. In other words I feel the light thud and can get the truck to just start to rock forward and back playing with the gas. If I shift into Drive, however, the tranny pulls great and shifts fine. After getting into 3rd gear, I can shift into OD and OD operates great. It will downshift into third, but if the speed is lower, it will just slip when dropping into 2nd.
I can rebuild chevy turbo 350s and 400 in my sleep, but this is my first a4ld and I know nothing about them.
Any help would be great.
Thanks in advance.

 

[Glacier991]

Sounds vaguely like a broken/breaking front one way clutch (OD sprag) issue. I have to think a little on these things, but if you lack OD 1st and have a manual 1st the difference is that the OD clutch locks up.... giving you engine braking..... lacking with JUST the front one way clutch.

 

[power67]

it truely feels like a pressure issue. When I first looked at the truck before driving. I put it into gear, OD and moved a few feet forward, put in reverse and moved back. Is it possible that one of the orings on one of the soleniods is bad? I did notice when I had the pan off that the fromt most soleniod was continuing do drip fluid from around the clamp point. I know it might be hoping and wishing but, the lady, her brother and boyfriend all swear that the tranny was fine in Sept. when they stoped driving it.

 

[Glacier991]

Well if my half baked theory is true, pressure has nothing to do with it. But also if my theory was true, your reverse should be impacted.... so I'm probably wrong.

Pressure is what makes everything work, and it would be helpful to have the line pressures... easy to do with a trans pressure gauge..... (about $35).

Search for Transmission Pressure gauge and you will find a thread I did on using one.

Servo replacement on these babies in vehicle is a major PITA.

 

[Bent Bolt]

O/D sprag failure. Coast clutch comes on in reverse ( engine braking )so a failed sprag won't effect that.