JL Transfer Case

GoHack

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My JLU now has over 4200 miles on it, including both highway, off road, snow and ice covered roads.

The 4Hi works OK now w/use, though I've had much better transfer cases which you could easily shift into 4 Hi w/just your finger vs. using the force of your arm, but it does work.

I would assume the issue is due to Jeep going back to their front axle locking actuator, which from past experiences when they used a similar design on their earlier Wrangler models, were just as much a pain to operate.

Toyota used a similar design as well, which you could by-pass the vacuum lines, and keep it locked, as well as add regular locking hubs to the wheels. A '91 Toyota 4 Runner I once had, had such a design, but once modified, it was like day and night when it came to shifting into and out of 4 Hi. I also gained as much as 2-3 mpg, thanks to the added locking hubs, allowing no axle movement.

Anyway, I'm still having an issuing getting into, and out of 4Lo on my JLU. The front axle locking actuator should already be engage when in 4Hi, but going from Hi into Lo takes a lot of brut force, and a little grinding. When off road, I try to throw it into 4Lo for a few miles in order to get things broken in. While 4Hi is working better as it gets used, 4Lo doesn't appear to be the case. When going into LO, I try to be on a decline, allowing for a little movement for the gears to mesh.

With this transfer case being cable operated, is there a cable adjustment needed?
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Jeepsterfreak

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That’s an interesting observation. I honestly don’t know if the FAD is causing your transfer case symptoms. I wouldn’t think it would knowing the way it operates. All it does is slide a locking collar to connect the passenger side intermediate axle to the outboard axle making it one. There are splines on the axle and teeth on the collar. The collar won’t engage until they are lined up. But the collar is moved via an electric motor so I wouldn’t think it would cause you to feel binding in the transfer case.

I suppose you could test it by disconnecting the wiring harness from the FAD while in 2H and then see if it shifts into 4H and 4L any easier.
 

AlamedaJeep

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Just curious, are you comparing your transfer case to other Jeeps or those from other manufacturers?

Mine operates exactly as you describe (takes more than finger pull to shift into 4H, and 4L requires more force and sometimes a little grinding). Every Jeep I've ever driven has been exactly the same.
 

DeVoTee

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I was having the same issues with the transfer case, but it is starting to loosen-up a little. With 4 Lo rolling at 1-2 mph helps.
 

Swanny297

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My JLU now has over 4200 miles on it, including both highway, off road, snow and ice covered roads.

The 4Hi works OK now w/use, though I've had much better transfer cases which you could easily shift into 4 Hi w/just your finger vs. using the force of your arm, but it does work.

I would assume the issue is due to Jeep going back to their front axle locking actuator, which from past experiences when they used a similar design on their earlier Wrangler models, were just as much a pain to operate.

Toyota used a similar design as well, which you could by-pass the vacuum lines, and keep it locked, as well as add regular locking hubs to the wheels. A '91 Toyota 4 Runner I once had, had such a design, but once modified, it was like day and night when it came to shifting into and out of 4 Hi. I also gained as much as 2-3 mpg, thanks to the added locking hubs, allowing no axle movement.

Anyway, I'm still having an issuing getting into, and out of 4Lo on my JLU. The front axle locking actuator should already be engage when in 4Hi, but going from Hi into Lo takes a lot of brut force, and a little grinding. When off road, I try to throw it into 4Lo for a few miles in order to get things broken in. While 4Hi is working better as it gets used, 4Lo doesn't appear to be the case. When going into LO, I try to be on a decline, allowing for a little movement for the gears to mesh.

With this transfer case being cable operated, is there a cable adjustment needed?
You sound versed in 4WD you are shifting in and out of 4lo in neutral right?
 

Jeepsterfreak

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This is from the owner’s manual. Tranny should be in neutral or clutch pressed. Do not pause in N when shifting. Go straight to 4L. Don’t know if this will help.

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GoHack

GoHack

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When operating my JL, I come to a complete stop, while in 4Hi, preferable on an decline, I then shift it into Neutral, and then try to go into 4LO, w/the vehicle moving a little, thanks to the decline, so the gears mesh, which helps a little, but not always, to get into Lo.

On a flat surface, in Neutral, w/o any way for the vehicle to move, is one BIG pain in the ass, and I generally have to go back into 4Hi, and then find a decline someplace.

I've owned several 4x4's, including a 1978 CJ7, several Wranglers (1989, 1991, 1994, and a 2006) as well as a couple of JK's. I don't recall any of them using a cable mechanism in the transfer case, but instead a direct linkage. As such, could the cable be out of adjustment?

The 1989 through 1994 Wranglers I've owned used an axle disconnect mechanism, similar to what the JL again now uses, but using a vacuum actuator to engage the complete axle (L & R) vs. an electrical servo now on the JL, and once engaged, allowing for the driveshaft to move. Until the axle mechanism is engage, the driveshaft won't start moving, allowing for the gears in the transfer case to mesh.

The 2006 TJ, and the later JK's, had no axle disengagement, thus making it easier to get into 4Hi, since the driveshaft is always moving. The CJ7 didn't as well, but also included locking hubs, which helped in getting better fuel mileage, since you could disengage the complete front axle from moving.

I also don't remember going into 4Lo as being such a pain in the ass as the JL is on any of them. Yes you had stop, or a near stop, but they still shifted into Lo a lot easier than on the JL.
 
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