Your first sentence talks about the terra grappler, then you say you got 45, and that it's a mt...the terra grappler is an all terrain. Did you mean the trail grappler?

 

I edited my post to clear up the confusion...sorry.

 

Thanks for the info, good to hear some getting 45 out of the TG's, I'm thinking that's what I will run when I'm done with the stockers. Do run mostly on or off road for that 45? Thanks again.

 

It was a fair amount of two tracking and highway miles.
40k highway, 4k city and the rest off road at the hunting property.

 

What would bigger tires do to my mpgs

 

I don't know on the 6.7 as I bought the truck with the bigger 35's on the truck. I know on my last couple of trucks it will decrease mileage by 1-2mpg. There is more rotating mass...you are going to pay for it at the pump.