Auto trans won't shift

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Sep 28, 2022 | 02:11 PM

JWMJR91F250

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4wd Low

Joined: Aug 2022

Posts: 11

Likes: 2

Auto trans won't shift

I'm registered with my '91 F250, but also own an '89 B-II XLT. I've owned this awesome little rig since 2000. Recently it won't shift into 2nd when in D or OD position. After about 5-10 minutes it will begin to operate as normal. I can start out in 1, shift to 2 manually, all gears work. I recently had trans flushed and new synthetic fluid, they said it was fine since Mercon not common any longer. It was doing the same thing before the fluid change. It operates great after it gets good and warm. Fluid is full, not low. Has 237,000 miles on original trans, etc. Is there a sensor or module that could cause this non-shifting issue? I realize it could use a full rebuild, but hoping something possible to fix it. Thanks all.

Sep 28, 2022 | 03:51 PM

Mark Kovalsky

Frmr Ford Trans Engr

Joined: Aug 1999

Posts: 24,739

Likes: 2,669

From: SE Florida

There are no sensors or modules that control this transmission. It is all hydraulic.

Chances are you have a sticking 1-2 shift valve in the valve body.

Sep 29, 2022 | 02:31 PM

JWMJR91F250

Thread Starter

4wd Low

Joined: Aug 2022

Posts: 11

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Hi Mark, thanks for the reply. I also asked a friend and he said it could be "solenoids" in the trans. Could this be the same thing you refer to as "shift valve" in valve body? My regular mechanic asked his trans mechanic and they told me can replace "solenoids" for about $500 but doesn't guarantee that will fix it. Also quoted me about $2,400 for full rebuild. Would you try the shift valve/solenoid repair if it was you?
Thanks.

Sep 29, 2022 | 02:42 PM

JWMJR91F250

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4wd Low

Joined: Aug 2022

Posts: 11

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And just to confirm, we are talking about the A4LD trans.

Sep 29, 2022 | 02:43 PM

Mark Kovalsky

Frmr Ford Trans Engr

Joined: Aug 1999

Posts: 24,739

Likes: 2,669

From: SE Florida

I can guarantee that the problem is NOT the "solenoids" in the trans. Your transmission has two solenoids, one locks the torque converter and one makes the 3-4 shift. There are NO solenoids involved with the 1-2 shift.

I would try the 1-2 shift valve in the valve body repair, but I wouldn't have someone that thinks non-existent solenoids are the problem do the repair. I'd find someone that isn't trying to rip me off. Quoting $500 to replace solenoids that don't exist doesn't seem right.