Can't get her into 4WD (3 Viewers)

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I know there's lots of threads on this topic, but i think i've read them all.

I either can't or don't know how to get my '68 FJ40 into 4WD. Transfer case and transmission have been completely rebuilt by our friends at Valley Hybrids so it's not suspect, and it used to work. Here's what i've tried:

Transfer case in 4H, transmission in neutral, front hubs unlocked. pull the FD button and i get a very brief, faint flicker on the FD light and it doesn't light. i've pulled the cover off the vacuum actuator at the transfer case and the lever is going back and forth as it should. Front driveshaft still spins freely.

what am I missing?

thanks in advance.
 
sometimes if you rotate front dline by hand just a bit then try again, and so on, it will find a happy spot and lock in.


The OP did say the lever inside the actuator moves forward and backwards and front driveshaft spins freely. Engaged in 4Wd with the wheels on the ground and rear driveshaft installed front driveshaft shouldn't spin.
 
Is this vacuum activated? Yes - how is you vacuum. Maybe it isn't sucking hard enough to fully engage.
Turn the hubs in and put tranny in first and barely start moving forward (mash in on the clutch) then engage the button.
 
Is this vacuum activated? Yes - how is you vacuum. Maybe it isn't sucking hard enough to fully engage.
Turn the hubs in and put tranny in first and barely start moving forward (mash in on the clutch) then engage the button.
great idea. but i did take the cover off and remove the control arm and was able to manually push the plunger back and forth. still no light or 4wd.
 
Drain tcase, remove skid, slide under pass side, take the 4 bolts off the housing on the side of the nose cone just under the vac accuator, sometimes there isnt enough space to get the fork all the way out because the tcase is close to that frame rail. When you say used to work, that was before the rebuild ?
I suppose anything is possible
 
Four bolts will remove the actuator off the transfer case. The fork will be the part that goes into the transfer case. You need to be sure it fits into the groove in the collar that locks the front output shaft onto the main shaft which goes all the way out the back of the transfer case. The collar connects the two and put it into 4WD.
 
It my understanding it use to work, so something happened - vacuum leak, grease dried up, a slight burr on a shaft/gear during last use, some adjustment slipped a little.
 
Drain tcase, remove skid, slide under pass side, take the 4 bolts off the housing on the side of the nose cone just under the vac accuator, sometimes there isnt enough space to get the fork all the way out because the tcase is close to that frame rail. When you say used to work, that was before the rebuild ?
I suppose anything is possible
really appreciate this. i'll try it.
 
It my understanding it use to work, so something happened - vacuum leak, grease dried up, a slight burr on a shaft/gear during last use, some adjustment slipped a little.
to be clear, when i say it used to work, i honestly am not sure it was ever actually working but at least the light came on when i pulled the FD knob.
 
On my 68, pull the knob if the green light doesn’t light, just drive forward a bit and it engages…..about a 50, 50 chance the splines are lined up to allow the cog to slip over the splines.
Also, I engage the hubs befor pulling the knob. Originally, when you pulled the under dash lever to low range, there was a linkage that pulled the knob out to ensure you were in 4WD in low range….mine abandoned been removed.
 
Right after I bought it, my FJ40 front wheel drive engaged fine for a while, but it started to "jump" out of 4WD and then no longer functioned.

I then discovered the PO had some knucklehead "rebuild" at least the front "nose cone" assembly of the transfer case, who left the front output shaft bearing retainer snap ring out, rather than back in the nose cone. Every shift into front wheel drive pushed the unretained bearing out of its seat, little be little. By the time I found the problem, the bearing had pushed out the seal and gear oil was starting to leak out. :bang:
 
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Right after I bought it, my FJ40 front wheel drive engaged fine for a while, but it started to "jump" out of 4WD and then no longer functioned.

I then discovered the PO had some knucklehead "rebuild" at least the front "nose cone" assembly of the transfer case, who left the front output shaft bearing retainer snap ring out, rather than back in the nose cone. Every shift into front wheel drive pushed the unretained bearing out of its seat, little be little. By the time I found the problem, the bearing had pushed out the seal and gear oil was starting to leak out. :bang:
Eeeoooowwww, bad JuJu…..it was repairable, I hope……PO stories are the worse….but part of ‘your’ Cruiser history….saver the knowledge there are FJ40 ignoramus’s out there……that still think you’re driving a ‘J$&p’ (that’s a 4 letter word that cannot be repeated on this forum🤣🤣🤣)
 
The 4 bolts hold the housing that contains the rail and fork, not sure what holds the vac accuator on or if it has to be removed to get the fork housing off.
 
Don’t go by the light. It could’ve burned out, bad path to ground, etc.

Pretty sure hubs unlocked, trans in neutral, you can still spin the front driveshaft by hand in 4wd because there’s nothing stopping it from spinning.

Lock the hubs, put it in 4 and drive it, turn tight, you’ll know if it’s in 4 or not.
 

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