diesel fuel

When I hauled RV's all over the US, I had a place in Mich rebuild the pump in my Chevy, and they recommended a mix of cheap auto tranny fluid and Power Service. I used the small Heet bottles and refilled them with mix and a bottle went into each side tank every fillup. Never had a problem after that with the pump/injectors. It will clean up some of the smoke and make a little more power but in the winter it was always plugged in. If you ever have to buy a diesel starter ($$$) you won't want to do it again. Plugging it in just helps the whole starting process.