O/D light flashing on 96 explorer 4.0 4x4

[Apple]

I have a 1996 explorer with 4x4 with the 4.0 and auto tranny,261,000 miles (I think its the 4r44e but not sure). Last year the torque converter started to unlock and lock back up right away about 3-4 times each way in a 17 mile drive to work. About 2weeks ago my wife took it to town and on her way home it quit going into overdrive. I took it out the next morning for a drive around the block and it shifted up thru the gears fine, but no overdrive, the O/D light was flashing the whole time. When slowing down it had one hard down shift and the others were normal. At the next corner just as I let off to slow down it shifted into overdrive and downshifted normally coming to the corner. I stopped and checked the codes and (I can't remember the code number right now) but said Input turbine speed sensor circuit. I cleared the codes and started driving again. The O/D light was off but it was just slamming into the next gear really hard at a slow speed and after about 30 yards of driving the O/D light started flashing again and shifted normally from 2-3 but would not shift into overdrive again. I was going to replace the epc solenoid but they are $385.00 thru Transtar, and thats alot of money if I am wrong. The input speed sensor would be a tear down on the tranny. Any help would be great. I really need to get this back on the road. I have found another trans for $525 Would that be the better way to go? Or does this sound like it is the epc solenoid?

 

[Viper Command]

you have a 4r55e.

to me it sounds like a line pressure issue. it could be the solenoid, but when the od light is flashing its telling you its in safe mode and bumpes up the line pressure.

If it was my trans, I would be looking for a leak (internal) like the vb gasket or seperator plate. there is something bleeding off pressure.

also I have seen a clogged filter do the same.

 

[Apple]

I have the valve body off and have not found any bad spots in the gasket. I know that it was way over due for a fluid and filter change. I'll try and get it back together this weekend and see if that took care of it. Thanks alot.

 

[Viper Command]

be shure you replace the gasket (even if it came off in one peice)....

there is a small crap trap filter near the corner be shure its not clogged.

 

[Apple]

I have went ahead and ordered both valve body gaskets and waiting on them to come in. I didn't know about the small trap screen. Thanks! I hope this takes care of our problem. I'll post after all the parts are in and I get it together and tested.

 

[Apple]

I put in the two new valve body gaskets and new filter and the problem went away I believe the valve body to seperator plate gasket had a blow out in it. Thanks alot for the help on this.