2025 Laramie with Twin Turbo 6 engine tune, Cat6 or JBL4???

[Laramieblue]

I am not a high speed junkie but retired and like to get better mileage on highway that is greater than my 17 mpg. When I tow a 5,000lb travel trailer I usually get 8-9 mpg going around 60-65 mph on highway with cruise control on.
Has anybody installed an engine tune package that has increased their low rpm torque and hopefully mpg as well?
I am hoping that having an increase in low rpm torque will lower my cruising rpm and thus increase my mpg.

 

[Laramieblue]

Here is the response to my email to the JBL4 folks:
We don't have any dyno data using 89 octane, you need to use 91+ or better with the Jb4 installed & turned on. The JB4 does not alter or change the OEM TCU / transmission mapping, that will stay the same. Generally speaking under normal driving scenarios expect MPG to say similar / the same. Under WOT / heavy acceleration periods MPG tends to decrease with the added HP / TQ demands.

It seems like the only option for utilizing the JBL4 tune is to run 91 octane, for a 33 gallon gas tank that will increase the cost to fill up by around $18 and still no guarantee I get enough mileage to cover the cost of the higher fuel cost.

 

[CalvinC]

No tune will improve mpgs despite the marketing hype. Your most economical tune is the factory tune combined with a deliberate right foot.

If tweaking a few lines of code would have netted more mpg you can be sure the OWM would have done it to earn more Greta points.

Tunes on modern engines get more power by adding timing and boost.

More timing requires higher octane fuel, which is why they don’t bother with lower octane fuels.

More boost requires more fuel to suit, less you run lean, which is why no tune that adds power would also improve mpgs.


All that said, tunes are fantastic for many other priorities, and I would not hesitate to use a Jb4 if I owned a Hurricane (though I’d drop it for true custom tuning if/when that becomes a possibility).