"4X4 Not Available" message

[Msu50000]

2023 Lariat 5.0

4x4 has worked great all summer at the dunes, until a couple of weeks ago. Slight incline out of the dunes and message comes up saying "4x4 Unavailable" and front 2 stop spinning.

Switching in and out of 4H didn't help. 4A didn't help. Turned truck off and on, no change. Kept it in 4H and crawled out in basically 2H as only the rear wheels were working. As soon as I was in a spot where basically there was no need or load on on the 4x4 system message came back up stating "4x4 Restored". There is no grinding sound, or pop, or clunk, or anything when the system engages and disengages that I can hear. Like I said, it feels like anytime there's a load(need for them to spin)on the front wheels the system drops out, then come back when I don't need it.

I've been able to recreate this multiple times on the dunes. Dealership could not in town. Forscan didn't show error codes and dealership didn't see any. Any idea what it could be? I don't think my truck has IWEs (4A t‐cases have EIWEs?), anything else it could be? All new fluids front/rear diff and T-case.

Sponsored

 

[Goldeneye36]

If I had to guess - The TOD (4A) transfer cases use clutches to engage 4wd, even in 4H, so you may have overheated them on the dunes, causing them to slip and lose engagement until they cooled off. The ESOF in the lower trim trucks and the Hi-lock in the Raptors/Tremor are mechanically locking and don't have that issue.

The TOD transfer cases are great as an all-around solution since a lot of people don't do serious off-roading and being able to use 4A on pavement is nice, but the main downside is what I described above.

 

[Msu50000]

Thanks Golden, any idea on how to convince dealer to warranty the transfer case?

 

[Davexxxx]

Thanks Golden, any idea on how to convince dealer to warranty the transfer case?

Sounds like it went into a self protection mode so, functioning as it should.

Even older style, mechanical 4WD systems, electrical, or even manual, don't want to engage (or disengage) while in much of a bind.

 

[Msu50000]

Sounds like it went into a self protection mode so, functioning as it should.

Even older style, mechanical 4WD systems, electrical, or even manual, don't want to engage (or disengage) while in much of a bind.

We're only moving about 15-20mph on soft sand, shouldn't be much binding in the 4x4 system. Tires will initially have power going to them and then stop, I think Golden's suggestion that the clutches inside are wore out is probably accurate. The fluid I drained from the t-case was really bad/stinky/gray at only 35k miles. I think prior owner(s) may have driven around in 4h a lot when not needed.

Sponsored