I used to get 15mpg almost dead on every tank. I always thought that was a little on the low side, but it's a 4-door 4x4 with 33x13.50-18's so I guess it wasn't terrible. Well the last two fillups I've only got 12.5-13 mpg and I haven't made any changes to the truck, all the filters are pretty new. Any ideas?

Mark

 

Where do you live? Do you always fill up there, maybe you got a hold of some winterized fuel it will do that. How long has it been since you cleaned your ebv tube?

 

Have you noticed less boost with the last two tanks?

 

I cleaned the EBPV tube and put a new sensor on about 2-3 months ago, the truck rarely sees full boost with fuel prices like they are, but they still peak around 22-23psi like always.

I own a gas station so I only buy diesel at my store.

 

Lift the vehical, spin the wheels, look for drag, check up pipes for leak. just a couple of thoughts