I ahve an 01 3500 dually 2wd. I dont have any power.. I recently hauled a trailer/load of 9000lbs. and barely reached 65 floored and got approx 6 mpg. I barely break 11 empty with the inside duals taken off. Any suggestins on what I should do??? Dodge cant seem to find anything wrong with the truck!!!

 

your transmission shifting ok? or is it lugging? with it "floored" does the trans drop down a gear and RPMs go up?

 

check your cats to make sure they are not plugged. you should have 3 of them, 1 ea right off the exhaust manifolds, then 1 on the main exhaust tube. Then swap or clean your o2 sensors. you might want to also check your plenum gasket for leakage, it is a known problem and causes poor performance.

 

Like Steve00ram360 said. It really sounds like plugged cat to me. According to a mechanic I had a conversation with when I replaced mine, a cat will be hotter at the back end if it is working correctly because the exhaust is pulling heat out the exhaust pipe and hotter at the front end if it has plugging issues because the exhaust can't get into the cat. If you have access to a temp sensor you might use it to analyze your cats.