Ghost shudder

[lightninmike]

While driving on the highway and the cruise control set at about 70mph the truck runs fine. When climbing a hill and getting to the top where the drivetrain will unload the truck will shudder for a few seconds. It does not do it when the truck puts the engine back under load when getting to the bottom of the hill and back to flat ground. Anyone have any ideas on what the heck is going on here? The truck is well up to temp before i get to the highway if that would factor into it in any way

[SCUFFY828]

a possible egr valve problem, may want to get codes pulled and see if anything is setting a code

[lightninmike]

No light but ill put my scanner on it and check it out. Thanks man