I'm new to board, so excuse any repetition of other post. I have a 2000 QC 4x4 5 sp sb 5.9. About a month ago I noticed that as you excelerated in 3rd fairly slowly up to 2000-2100 rpm's then steppedon it ,it went to about 2500-2600 and smoked out tailpipe, and wouldn't pick up any more. I changed air filter and fuel filter, still did it. It was very noticable getting on onramp in 4th pulling my 7500Lbs Bobcat. Anyway, I had a lot going on at that time and didn't take it to dealer for repair as it had 45 K miles, well I have time now but it will not repete the problem, Does anyone have an idea what was going on , or what I should do? TKS Nat

 

Could be something as simple as a bad tank of fuel. Sounds like you were adding more fuel than you were burning. Make sure all the pressure system clamps are tight from the turbo to the intake. Getting black smoke is an indication that the engine detected adequate boost and allowed the engine to continue fueling, hence the smoke. Bad or low cetane fuel can cause the problem you had.