My truck (2019 Classic) runs horrible with the ECO mode on. I keep getting a rumbling sound and hesitation coming out of the ECO mode. The dealership tells me it is a characteristic of the truck. What a crock, especially since they said this happened on older trucks with the 5.7 and there was a computer update that fixed the problem.

Meanwhile, I've been manually putting the truck in 8th gear, which temporarily disables the ECO mode and the truck runs better, but the tranny seems to wind down quicker.

Does anyone here use a tuner to permanently disable the ECO mode? And with that said, are there any tuners out there that won't break your wallet?

Thanks in advance ...