I have purchased a 2006 Freightliner Century 120 with Detroit 14l with Ultrashift. I have it singled and flat bed installed. Carry a Smart car behind cab and tow my 40' 21k Teton 5th wheel home behind it. It has 750kish. Runs great but my wife follows me and says it rolls black smoke when puling up hills. Why is this? Now I did install the Ugly Stick and that is all I will say since I understand we not allowed to discuss this. I have not drove it since. I have not towed camper yet. Initial drive was bobtail.When cleaning up truck I found the fire extinguisher compartment was oily when previous owner had been storing jugs of oil. Do I have a problem?
Rolling black smoke is an indication the engine is pulling hard, are you lugging in too high a gear?? Gray smok = oil Light mist = unburnt raw fuel ... Philip
If its excessive smoke, could also be the little rubber boot in the injection pump blown? Older trucks will smoke some though, especially if being lugged. If it uses a lot of oil, probably needs a Ring job.
