I have a 2005 GMC 3500 dually pulling a fifth that can weigh upwards of 12,000lbs. Coming home today on 1 with the Edge I got to 1350 without pushing too hard. The grades were 8-10% a couple of times. After looking at what I have done what else can I do to economically help lower these numbers. I constantly see 1200-1300 degrees on level 1 towing.

Should i put it in stock level and push the boost more? Would an exhaust help lots or little?

Any suggestions?