Ok, seems like about every third tank I have to add SeaFoam to my tank or my mileage drops down 1-2 mpg. I add 2cyl oil with 90% of my refuels (1oz per gallon).

Is there something else going on?? The truck has 275,000 plus miles I dont know what was done to it before I got it. So I don't know if it has original injectors or if they've been changed.

-Tim

 

At 275 K plus I would certainlly recomend injector replacement. Mine had been giving about 15 MPG for 70 K miles, pulling trailer. Developed bad miss and diagnoised as injector. Purchased standard aftermarket set from Pensacola Diesel for 217. Installed and fixed issue. Regained or improved on power as they suggested. Fuel milage hit over 20 calculated for 1200 miles so far. My recomendation is replace injectors even though don't notice a performance problem. Another 3000 miles the injectors are fully paid for. Unbelievable.