The day started out well and went down hill from there, the FJ40 is now stuck in reverse (1 Viewer)

[21NDone]

Started the day preparing for a Dakotas Digital RTX install by replacing the the water temperature sensor and the oil pressure sending unit. Because I want to do the DD install in steps and because I'm waiting on some color coded wiring I decided to hold off going further with the install.

Took the FJ40 to check the mail only to notice they were still stuffing boxes. OK, I'll come back later to get the mail. As I was leaving the parking lot in 1st gear and about to shift into 2nd I realized I couldn't get the shifter in second so I stopped - in the middle of the road. I was able to get the truck in reverse so I backed up to the parking lot to get out of traffic. This is where I realized I couldn't select any gear and the transmission was stuck in reverse. Clutch operation still disengages but when released the truck go backwards.

Fortunately I live in a sleepy town and there's very little traffic, so I drove about 3/4 of a mile in reverse to get home - check that box

Did some quick Mud searches and realized I'm not the only one who's experienced this 'feature' of the FJ40. There is very little play in the shifter in any direction.

I'll keep researching but I'm all ears for anything that will get me back to a good place. The DD install is now on hold until this condition gets resolved.

Truck:
1975 FJ40 (2/75 build)
Manual 4 speed on the floor
Clutch engages, disengages and is fully serviced with fluid
No running gear mods that I'm aware of
No indications, sound or otherwise, this condition was immanent

 

[Mark Jennings]

Looks like it’s time to pop the cover off the transmission…..pictures of what’s affecting its innards are required.

 

[Av8erB]

Yikes that doesn't sound fun. While you're down there maybe switch it to a 5 speed.

 

[Pighead]

Sometimes, just pulling the stick out of the tranny, fiddling around with those sliding thingies down there, you can get it back into neutral. then re-inserting the stick will fix that

 

[21NDone]

Exercised my search skills and came across a thread that looks promising wrt a path forward. The cover will likely come off but am curious what I will see with the shift stalk out.

 

[21NDone]

Dove into the shifting issue further and this is what I saw when I removed the shift cane:



The FSM didn't describe or show the orientation of the gears when in neutral. My novice eye thinks its in neutral, am I correct or? If it is in neutral, what would my next step be isolating why the trans is stuck in reverse?

 

[21NDone]

Manually cycled through the gears the best i could with a big screwdriver, played with the reverse detent and aligned everything for reassembly. Stuck the shifter back in and cycled through the gears and everything seemed fine. Took for it for a ride and shifting gears was smooth. Not sure I can call this a complete success because I'm not sure why it got stuck in reverse in the first place. Cheap win but I'll take it.

 

[Pighead]

I'm not sure why it got stuck in reverse in the first place.

I'm not sure why it happens either. All I know is that sometimes it happens. Make sure those two roll pins that hold the cap on are tight and in all the way. But now you know how to fix it so it probably won't happen again.

 

[3_puppies]

try to use a square shift pattern when shifting
3 movements
versus diagonally

 

[bdog75]

I swapped a transmission one time and it did not have one of the detent balls under the top cover to keep things in check. I got really good at popping the floor shifter out with two screw drivers, re aligning and re installing before the stoplight would turn green.

 

[Mark W]

I have seen this happen a couple of times. Both times to the same rig. Years ago. The girl who owned/wheeled the rig had a bad habit of hanging on to the gear shift. Not just keeping her hand on it, but hanging onto it to help stay in her seat while bashing over rough terrain. It seemed that there was just enough wear on the tip of the gear shift lever and just enough slop in the gates that when she yanked it just right she could pop the lever into the next gate without pulling the shift rail she was leaving far enough to keep the detent from pushing it back. The result was the lever being in the gate of the next rail that was locked in place by the safety interlocks while the original gear was still engaged. In her case she was yanking out of third and into second if I remember right.

I just pulled the shift lever out, shifted it into neutral with a screwdriver and she was on her way. Not sure if she ever broke that habit but at least she learned how to fix the resulting problem.

In your case I would guess that a slightly over enthusiastic pull at just the wrong angle and just enough wear in the tranny resulted in the same thing happening.

Mark...

 

[FJ404345]

^^ think we are on to something here

 

[65swb45]

It doesn't help when one or both of the pivot pins in the tower wears down/gets loose. I've seen a LOT of worn pins over the last five decades. Fortunately, the tower pin repair kit $OR sells for the 3speed tower will also fit the 4speed tower.