I can get over 20 easily in my 2011 ram 1500 with a 6.4SRT8 short block, cam and eagle heads, Vararam intake cruising at 70MPH but I bet the NOX is too high for EPA. It does need premium fuel. My new truck is a 2011 dodge 2500 long bed crew cab and I have settled on building a BGE short block, eagle 5.7 cam, intake and heads, hoping to still get 20 MPG with it. I have run out of money to address the lack of quench on this one also so it just is what it is, pistons about .020 in the hole .035ish head gaskets.