After reading many threads on installing 35" tires, it seams that the ECO/MDS will never kick in With any of the stock gearing. even 3.92

What's the real MPG for this truck and can this be corrected to get the ECO to kick in?

Thanks

 

I have 37x13.50R18 tires on my truck and the MDS operates as it always did before I installed the larger tires.

 

very true. If you are worried about mpg then buy a car. And if you are worried about mpg but have to have a truck then stick with the stock tire size