Power Loss I have 2001 Chev 2500 hd Dura max Diesel When you start up a hill it runs fine then it will lose power .You Can Change Gears It still Want Get Over 1800 rpm. you will have to cut the truck off and wait a little while the restart and it will run fine on level ground 90mph or more . It did not do This before . Ihave changed the Air And Fuel Filters.

My guess is injectors. The early duramax's had a lot of injector problems. They sometimes get to where they bleed constantly, and sometimes they break off... bad stuff. Check your oil for diesel. When my dads injectors when out on his 01 D'Max, his truck would run ok for a while, then lose power. Computer will cut power when it picks up an injector problem. BTW, Sightseer, diesels dont have spark plugs, however, the diesel filter is a good idea, you have to change them pretty regularly on the D'Max engines ( in order to try and prolong the injectors lives, mainly, the smallest bit of junk in your fuel can screw those early injectors up quick) I think they got the injectors mostly straightened out in the 04 models, what I've heard is thats the best model Duramax there has been, fuel economy, power, and reliability. Too bad all the year models arent that way :/