tdiot

My father-in-law has a trucking company that runs a fleet of Dodge Cummins the odd Duramax, Peterbilts and Freightliners. According to him fleetwide his spreadsheets show a 10-20% mpg drop over the last year. He is not happy at all.

proudpapa97

PatDaly,
Thanks for your added info and encouragement.

Do you know how I would find out if there is a DTR Chapter in Phoenix, Arizona, and how I would go about joining??
Thanks,

Tate

https://www.dieseltruckresource.com/...play.php?f=126

thewished

My shops average drop between us all combined is around 3 mpg of diesel. So YES crappy fuel will considerably drop your fuel mileage. It helps to run additives and some 2stroke oil every once in a while. I myself run it everytime I put more than $20 worth of fuel in my truck. Especially since winter blend diesel is only good to 10*F before it gets bad. I know it would help to adjust my timing but with just bad fuel it has been bad lately.

infidel

My feeling is this is due to sound traveling better though colder air.

walexa

I just figured it was piston rattle from a worn pump.........2 strokes rattle more when cold than once warmed up........just my guess though.

Mine rattled for over 50k miles until it gave up the ghost a couple months ago. No warning, just dead. These lift pumps don't go out often so I did quite a bit of trouble shooting before determining it was indeed the pump. I put a new one in and all was well. Ended up being the check valve(s) in the pump. I believe there are 2?

Waylan