[cummins12v]

my truck starts to run alittle rough at like 1300rpm whenever im in 3rd or 4th gear. or if i change a little early anyone know what causes this???

 

[1BadOilBurnerN-Lv]

prob because your lugging the motor :rof

 

[Joe G.]

Some aftermarket injectors can cause that. You should fill in your sig so we know what you have when you ask questions.

 

[cummins12v]

doesnt have any injectors yet havnt had time to put them in i figured something was wrong with the timing but i wanted to wait till i put the injectors to figure that out....my friend has the same truck and it doesnt do it and he has 215000 miles