Stuck in 4L in all lever positions (1 Viewer)

[JakeDHAC]

Hey guys! Wondering if anyone is familiar with this issue.
I just got an '86 FJ60, and I'm loving it! But when I went to test out the 4wd today, I found that the 4wd dash light stays illuminated now when I shift back to 2H. There's no resistance in the lever between 4L and 2H, but it's clearly not disengaging the front driveshaft. I verified the hubs are unlocked, and crawled underneath to see if the front driveshaft would rotate freely in 2H, but it's clearly still locked into 4wd. When I started driving, it's pretty clear that I now only have 4L l, because I can barely get up to 30mph in 5th gear.
I read some of the other forums in here about getting stuck in 4wd, but they all seemed to either have a lever that couldn't shift to the right position, or a transfer case with separate levers controlling the 2wd-4wd and the Lo-Hi settings. As far as I can see, mine only has one lever attached to the transfer case, and then there's a separate switch on the dash for 4H (that also doesn't seem to work, but that's a problem for another time).
Does anyone know what my next step should be to troubleshoot and fix this issue?

 

[Godwin]

Vacuum switching solenoid on the firewall for going between 2wd and 4wd has failed. Switch the vacuum lines on the two ports and you should be able to regain 2wd. Proper fix is to replace the solenoid.

Shifting between high and low range is mechanical and high-low shift lever may have become disconnected from the shift lever on top of the transfer case.

 

[CardinalFJ60]

Yep….happened to me years ago. Quick fix

 

[OSS]

If the truck was driven on dry pavement in 4wd, the front and rear driveshafts are binding up the works. (don't drive on dry pavement in 4wd). F and R spin at slightly different speeds.
Jack up one rear wheel and a front wheel to relieve the torsional stress. Then it should shift out of 4wd normally

 

[MoCoNative]

Vacuum shift 4wd was not common on the 60 in the US, the 62 did have it. Correct me if I am mistaken, but doesn't the transfer case automatically engage the 4wd vacuum diaphragm via a switch when it is shifted into 4low and overrides the dash button? Also the front driveshaft will not rotate if the front hubs are still locked, even if you have shifted out of 4wd.

On my 60 many years ago I was fooling around and shifted into 4low just to test it out not long after I got it. It got stuck. On the top of the transfer case, right side of vehicle the shift lever pushes or pulls on a lever. This lever is attached to a shaft sticking out of the top of the case, maybe 3/8" of an inch thick and is secured by a bolt that pinches the lever to the shaft. Inside the case the shaft has an arm that rotates when the top lever/arm is rotated and moves a dog clutch between the high and low gear sets. Between the two is a neutral position. The earlier transfer cases had this internal arm sit on top of this shifting mechanism. On the 60 cases the internal arm is dangling under the shifting mechanism and is supposed to stay in a groove and move it back and forth.

On mine, it appeared that maybe a washer or something had deteriorated and let the external lever and shaft drop down just enough that upon shifting it jumped out of the internal notch and could not get the case shifted. I had to move the exterior mechanism while lifting it up until I found the notch and could shift it back to high range. The external lever could loosen and let this fall down, but there is a grove cut in it for the pinching retainer bolt, so it had not moved. Hence my theory something wore off, or the internal arm is kind of weak, maybe they bend down over time.

Two options to fix, split the case apart, big job, proper way to find the failure. Or, the risky move, remove external arm/lever, and never ever let go of the vertical shaft, cause the whole thing will drop in the case, find the notch the internal arm needs to fit into, add some shims/washers to pull it up and reattach external lever and tighten down bolt. You might get away with some split retainer clips that you could slide in under the arm too without the risky drop s*** in the case maneuver. I got lucky, visegrips are your friend after you get tired with zero room to work under the truck, and I got it shimmed and it has been good for 20 years.

 

[JakeDHAC]

Thanks for all the replies! I'll have to check the solenoid as soon as I get the chance, and I'll report back. I've been traveling for work all month, so I haven't been able to do any work on the truck yet.

If it does end up being the vertical shaft that MoCoNative suggested, I'll try to find another thread on here with more details about fixing that, because I don't trust myself to do it without dropping the thing into the case and causing a much bigger problem!