Just add a programmer, any one that have a decent 75-90 hp and the larger tires aren't even noticed. I ran with htech on 3 for 40000 miles (even towing 15,000) with 3.73's and 315 w/6" lift and never even though of going back. I only changed to 4.11's because of my 15,000+ trailer weight, but it was not totally nessary I just wanted higher rpms in OD when going up the hills to help the egts and transmission hunting.
I still averaged 15-17 for normal driving, 17-20 on the freeway, and 9-15 towing depending on weight. Also with the programmer the truck was pretty quick for its size.
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