Need some diagnostic help with a 1992 Explorer A4LD

[dave8351]

For the past few months I've been having a fairly regular problem with my transmission. When cruising around 30 to 45 mph the transmission seems to shift up a gear too high and the motor lugs. If I come to a hill or want to speed up and I give it gas it downshifts sometimes and then upshifts too early and bounces back and forth. Other times it stays locked in gear and won't downshift unless I really stomp on the gas. When it's lugging if I take my foot off the gas or brake the transmission stays locked in gear. If I brake to slow down/stop it almost stalls and then there's a clunk or bang and it shifts down. Sometimes I can catch it before it stalls and shift it into 2nd and it unlocks, other times I can't and it stalls out. And some times it works fine (not that often).

When I accelerate it usually has no problems, but sometimes I get upshift/downshift bounce for awhile around 35-45mph and occasionally at 50-60mph and is fine at speeds above 65.

I can start it in 1st and shift into 2nd and it runs with no problems until I put it in D or OD.

I have checked the vacuum lines, replaced the vacuum modulator, have no fluid leaks, replaced the TCC solenoid, 3-4 shift solenoid, replaced the TPS, replaced the VSS, adjusted the kick-down cable, adjusted the shift cable, adjusted the bands, no idiot lights, and seems to be independent of temperature - happens when the transmission is hot, cold, whatever.

I posted in another section of the forums & the governor could be causing some of these problems & is next on my list to work on. Can I drop the transfer case without draining it?

Could it be anything else? Any ideas/help with what's going wrong would be greatly appreciated!

 

[JK080]

The problem won't be with the governor.

In the valve body there is a valve in the upper left corner called the converter clutch shuttle valve behind the override solenoid, its spring is known to break and cause this valve to hang. This causes the converter to stay engaged.

 

[dave8351]

Dang, I really didn't want to pull the valve body again. Would that broken spring cause the rapid up/down/up/down shift problem as well?

 

[JK080]

Anything is possible, I just know for sure that it can cause the converter to apply and kill the engine.

There are other valves in the valve body the control the converter, there could be issues there as well. I would carefully check each valve and pay close attention to the converter related ones.

 

[dave8351]

Ok it's been several months since I've posted because I had to wait a few weeks to get the shift kit & as soon as I got the trans buttoned up one of the head gaskets's started leaking. I now have got everything back together and the original problem of a stuck torque convert clutch was solved.

However the transmission is now a semi-automatic, I put it in drive or OD and 1st gear works fine but it won't shift into 2nd, but if I take my foot off the gas and then put it back it shifts with no problem and it down shifts just fine. Manually putting into 2nd doesn't seem to work properly. Shifting into 3rd is no problem, but I have no overdrive. My dad was driving it like this for about 2 weeks, backed out of the parking lot at work, drove home and then went to back into our driveway and no reverse. We checked the fluid and everything is good.

Anyone have some ideas before I tear out and go over the valve body again?