A4LD torque-converter always locked?

[Joebigfun]

Can anybody comment on this A4LD problem? I just bought a '91 Explorer with an interesting problem. It is as though the torque-converter lock-up is permenently locked-up. If you start it and put it in gear, it lurches forward and usually stalls. If you can get it going it will stall when you come to a stop, like if you stop in a standard-transmission car without pushing the clutch in. I thought maybe the ECU was sending the lock-up signal all the time, so I replaced the ECU with a known good one. No change. Then I unplugged the 3-wire connector on the left side of the transmission, thinking if I killed all the power to the transm. the lock-up wouldn't engage. Wrong. No change. BTW, if I jack up the truck and put it in gear it will shift through all the gears like normal. I sure would hate to pull the transm. since it works fine otherwise. If you have any ideas please email joebigfun@yahoo.com. TIA! Joe

 

[SteveVB]

converter clutch shuttle valve or converter

Could be a couple of things

In the valve body the converter clutch valve could be stuck in the lock up mode. Pull the valve body and clean and replace the valve and/or spring.

Or the lock up piston in the converter itself is stuck on- in that case you have to pull the converter and replace it.

I would pick up an ATSG manual and try the valve body fix first. If not then pull the trans and replace the converter.

Good Luck.

 

[njsjfonline]

I would have to say it's the torque-converter
Im selling them for 2 years The only time i've seen that happen is the converter is shot.
Sorry And good luck
Sam

 

[Joebigfun]

Hey guys, thought I'd do a follow-up. After letting it sit all Summer, I thought I'd swap in a valve body out of a bad A4LD I had laying around. Sure enough, the prolem is gone. According to my factory Ford service manual, which addresses this exact problem, there are 3 possible causes. The first 2 are related to the valve-body and the lockup solenoid. The 3rd and least likely is the converter itself. So, since there is an abundance of bad A4LD's around, I highly recommend this fix to anybody having the problem. It isn't much harder than installing a new filter and pan gasket. Sure is cheaper than even the diagnostic charge a transm. shop will hit you for! And a lot easier than trying a new converter. Hope this helps someone out there.

BTW, this is essentially what SteveVB addressed in his reply. Thanks SteveVB

 

[doradexplorer]

I just bought a used 94 ex with exactly the same problem. Can you buy a valve body from somewhere, or is it something that can be easily cleaned to solve this problem? I would really like to get it on the road (I hate oldsmobile sedans!)
I tried the same computer/wiring check, with the same results. I would love to not drop the tranny, but i would also not like to not like to throw money into a valve body when it is the tc, so my question is is there a method of checking the valve body.
(Are there any differences in between the valve bodies of the other A4LD's [rangers/aerostars/etc])
Thanks,
Scott

 

[Joebigfun]

I'm sure a few members of this board will sell you a valve body from a bad A4LD. God know's, there are enough of them out there! I would rather spend $20-30 and try this than try the alternatives. I'm not sure about the cleaning repair.

 

[NH25]

As a matter of fact I have a used valve body from an A4LD. If you want it its yours. $30 + shipping. Let me know!

 

[doradexplorer]

Hey NH25-
Sounds pretty good to me, could you e-mail me the particulars on the tranny that it came out of, mileage, problem, etc.
my e-mail is megandscott2000@yahoo.com

I know the A4LD is kinda crappy, but what is it that goes wrong all the time (What I mean is, are there any problems with the valve bodies?!)

Thanks for the help,
Scott