at first i was gonna suggest you check your driveshaft for excess play, but on second thought you might be experiencing some wind deflection problems caused by the camper. i had a truck once with racks that went over the cab. at speed the wind coming off the windshield caused the front most bar on the rack to oscillate. a bug shield/hood mounted wind deflector might solve your prob.
where is the 05 cheverolet 2500hd knock sensor located 6.0 liter
Have vehicle scanned to determine the problem - usually either a defective gas cap or a problem in the emission control system
The Check Engine light is on because there is a problem with the emissions system. Once you have the problem repaired the light will go off.
The 2011 Chevrolet Silverado-2500HD has 16 valves.
The 2008 GMC Sierra-2500HD has a V8 engine.
The 2012 Chevrolet Silverado-2500HD has 16 valves.
The 2007 GMC Sierra-2500HD has 16 valves.
The 2013 Chevrolet Silverado-2500HD has a V8 engine.
The 2001 Chevrolet Silverado-2500HD has 16 valves.
The 2007 Chevrolet Silverado-2500HD has 16 valves.
The 2008 GMC Sierra-2500HD has 16 valves.
The 2005 Chevrolet Silverado-2500HD has 16 valves.