Fuel Issues with new 392

[Trek54]

Has anyone with a recent (2026) moab 392 actually had the issue " Wrangler Rubicon 392 may experience fuel cut-off or stalling issues, particularly on steep declines with less than a quarter tank, due to fuel pump module defects or fuel slosh causing the pump to suck air." Was this a fixed issue by jeep? Or does one have to decide to live with this possibility on a $80,000 vehicle? Thanks

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[aegisdrgn]

I suspect they didn't change anything to fix that. The fix would be lots of added cost for an edge case scenario the majority of their customers won't encounter.

 

[YGBSM392]

I don't have schematics of the fuel tank but I've always kept my vehicles at or above 1/4 tank to keep the fuel pump submerged and cooler.

 

[2nd 392]

The Chevy SB HP 6 quart “Trap Door” oil pan was designed to keep the oil at the pickup under both hard acceleration and deceleration. ….. also worked for uphill and downhill in my 63 Corvillys. Why couldn’t something similar be designed for the fuel tank ?

edit, yes they are available for fuel cells so it could be done.

 

[ag4ever]

I’d be more inclined to swap the fuel pickup filter for a hydromat.

https://www.holley.com/products/fuel_systems/hydramat/

I have notice my Moab has a fuel issue, I am having to fill the tank twice a week, just can’t resist listening to that engine sing.

 

[3TV]

I've never had this problem with 4 years of hard wheeling in my 2022 392. Most of the vertical stuff I do is in Moab where they can have some scary bad downhills on slickrock. And I've never had the problem with our 2026 392 Moab, which has also seen several wheeling trips to Moab. I can't imagine it is that common if you make a habit of topping off your fuel tank before leaving the highway, which is something I always do.

 

[Eleven71Design]

My 22-392 does show very low fuel when on longer inclines or declines. Fill up prior to a trip and I know there is 3/4 tank but it frequently will show under 1/4 or less. Never had it stall. Get to a flat spot and sit for a few minutes and itll show correct.

 

[yokramer]

The Chevy SB HP 6 quart “Trap Door” oil pan was designed to keep the oil at the pickup under both hard acceleration and deceleration. ….. also worked for uphill and downhill in my 63 Corvillys. Why couldn’t something similar be designed for the fuel tank ?

edit, yes they are available for fuel cells so it could be done.

Im sure any day now someone will design either a longer pickup for the fuel pump or a replacement fuel pump assembly with a sump in it.

 

[Pape]

Any 4 doors have the issue. My jk when 1/4 tank and park on front end incline was reading 1/8 tank. When at 1/8 it would occasionally stalls down hill after being park down hill for a while. There is probably something to retain the fuels around the pump but will drain if sit for too long in that incline. Never caused much issue other than me making sure to have more than 1/8 in my tank when doing that type of activity.

 

[Twisted10]

 

[alphawolff]

Any 4 doors have the issue. My jk when 1/4 tank and park on front end incline was reading 1/8 tank. When at 1/8 it would occasionally stalls down hill after being park down hill for a while. There is probably something to retain the fuels around the pump but will drain if sit for too long in that incline. Never caused much issue other than me making sure to have more than 1/8 in my tank when doing that type of activity.

the 392 has an even bigger tank than a normal 4-door, that combined with the uh... fuel economy makes it a risky situation. the pump has a bowl at the bottom to capture fuel in the event of a sudden incline event at low fuel, but it can only hold so much and the 6.4l just gobbles it down.

a possible solution is a pump with a much larger bowl, but it'd require completely redesigning the tank due to the larger required opening to install such a pump. not really worth it from a monetary standpoint when the solution is to just... not let it get that low if you know you're going to be on severe inclines for an extended period of time. if you're going wheeling you can just bring more fuel.

 

[Remorseless]

the 392 has an even bigger tank than a normal 4-door, that combined with the uh... fuel economy makes it a risky situation. the pump has a bowl at the bottom to capture fuel in the event of a sudden incline event at low fuel, but it can only hold so much and the 6.4l just gobbles it down.

a possible solution is a pump with a much larger bowl, but it'd require completely redesigning the tank due to the larger required opening to install such a pump. not really worth it from a monetary standpoint when the solution is to just... not let it get that low if you know you're going to be on severe inclines for an extended period of time. if you're going wheeling you can just bring more fuel.

Gas tank size is listed at 21.5 gal, the same as the regular 4 door.

2025 Jeep® Wrangler Specs: MPG, Towing and More

 

[alphawolff]

Gas tank size is listed at 21.5 gal, the same as the regular 4 door.

i was pretty sure the 392 has a 24 gallon tank, no?

 

[Remorseless]

i was pretty sure the 392 has a 24 gallon tank, no?

Nope, see edit to my post. Jeep.com says 21.5 for a 2025 (and I would assume 2026) 392 Rubi.

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