Have 02 DUALLY Diesel. Takes awhile to warm up to get it moving. Do warm it in neutral with parking brake. No power hardly in cold weather. Getting worse. Bad going up hills. Mechanic thinks fuel injector system rework. Son who has 2004 2500 Diesel thinks there is a trans line warmer or heater gone bad. Mechanic blank stare. 140k miles. Trans rebuilt around 60k. Been pulling a lot. Your thoughts?

 

Maybe stiction in yhe injectors? Might try stiction eliminator thrubthe fuel tank

 

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