I have bought a used Stealth standard model. I seems that on level 1 the motor is quieter then stock and at full gas it smokes less then stock. Is this the common result? I thought the stealth is a loud tune?

I either will run empty or pull a 6,000 lbs trailer. Does anyone have any experience on what power levels will yield the best MPG for each case. I don't run gages and the truck in other wise stock. I'm not looking for max power.

2002 2500HD LB7
Thanks,
Dan