Can someone point me to a video in how to shift?

[RickC137]

I bought a used 2019, 38k miles, previously owned by a woman near Miami.

I doubt she ever shifted it into 4WD.

On my first attempt, I thought the transfer case was damaged, it was that difficult to shift. Each subsequent shift has been easier, probably 7 or 8 times now.

When I get near 50k, I'll change all the fluids out for whatever the preferred synthetics are.

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[jeepoch]

The 392 has no 2HI position. 4 Auto, 4 Hi and 4 Low.

Miles, et., al.,

I have never had the privilege of driving a 392 so thanks for the education on the shifter labeling. Now I better understand the source of confusion. There is nothing that indicates 2wd from a driver's perspective anywhere within the 392 cockpit.

However, the '4 Auto' selection is where either 2 or 4wd is automatically selected based on any wheel slip. This is effectively the same as an All-Wheel Drive (AWD) system. On high friction surfaces, such as dry pavement, where there is no wheel slip - all four wheels are rotating at the same rotational rate (same rpm) - this is when 2wd is selected by the Transfer Case auto-magically. With any slip on any wheel however, the Transfer Case instead quietly selects 4wd under the covers.

Going even a little bit deeper beyond just the topic of 4wd mode selection, (and not intending to derail this thread) all JL's also implement comprehensive Traction Control (TC) in either the 2Hi or 4Hi modes. This is where the brakes on each wheel are also automatically applied to keep each wheel rotating at the same rate.

Recall, with open diffs, more torque is naturally applied (by design) to the slipping wheel on any axle. This is what allows the wheels to spin at different rates through turns. But with TC the brakes are applied in order to try and force an equal amount of torque to each wheel during slip when the driver's steering input is straight.

This braking technique is also the primary mechanism behind what is known as Brake Lock Differential (BLD). Brake Lock works independently on each individual wheel regardless of the 4wd mode. Think of Traction Control as being a BLD system on steroids when in the high gear. TC coordinates the braking action in concert over all four wheels when any slippage occurs in order to keep the vehicle going straight. But again Traction Control is only active in either 2Hi, 4Hi (or 4Auto).

In 4Lo however, TC is explicitly disabled, but BLD is not. Brake Lock Differential is always active except when lockers are engaged. When an axle is 'locked' both wheels on that axle are mechanically linked so they rotate at the same rate independent of any wheel slippage. But because there is no difference in speed between the left or right wheel, BLD is therefore naturally not needed.

For those JL owners without (or have dysfunctional) lockers, the BLD system still helps in saving the day. It by itself can help manage power to the non-slipping (gripping) wheel thus helping to pull the vehicle through the most difficult of obstacles. This is what makes the JL at any trim level so much better than any 4wd predecessor (Jeep or otherwise).

Granted there is absolutely nothing better than lockers for any type of extreme situation, still BLD is dramatically better than purely open diff axles nonetheless. So JL Sport pilots can still perform some pretty amazing Jeep maneuvers even without the locking axles.

Going even deeper, I still need to research whether the 392 has the same 'Rock-Trac 4x4' Transfer Case that's the exact same on all the other Rubicon Trims. Or whether FCA/Stellantis decided to throw in the 'Active-Drive' Transfer Case on the $80K 392 model. This top-of-the-line 4x4 system also supports the '4 Auto' mode but has more additional 4x4 behaviors regarding terrain selection. Unfortunately the current online documentation is not very clear. I'm beginning to think that the 392 is just another Rubicon but with the mighty Hemi V8. Personally, I can't believe this power plant is the reason behind the $30K price differential.

In summary I really hope this helps explain the 4x4 modes in general and what happens underneath your rig when each specific 4x4 mode is selected. Maybe this will help the OP be able to use his bad-ass 392 to it's fullest potential. Please however, all I ask is to still try and wave to us lowly but nonetheless way cool Sport owners. Especially on trail out in here in the wilderness.

Here is my 2019 Sport S just for reference. I use BLD in 4Lo all the time.

Best regards,
Happy Jeeping,
Merry Christmas.
Jay