has anyone tried the superchips mileage xs on a 2005 dak? Im looking for a way to improve my mileage because this 11.5 really isnt cutting it the way im going through my cash and how much I drive a day lol.

 

I don't have the mileagexs but i do have the regular 3865 Tuner.

I have tested the Mileage tune and wasn't impressed. Actually got worse mileage than stock.

So far the performance 91 has netted the best mileage, but it does require premium fuel.

 

Are you towing something? That seems really low. I use to tow a 2000lbs trailer and I was getting around 11mpgs. The other time I was getting around 11mpg was when my cats where clogged.

I've tried the milegage xs and I was getting about 17.4 with mixed driving. I'm running the 87 tune and I'm getting 16.2 with mixed driving. It seemed to work for me.

 

the pipes look fine, i installed a dynomax muffler about 2 weeks ago. The pipes coming out of the muffler are 2 1/4th in and the rest of the stock piping is 2 1/2". could that be affecting anything? I think im going to blast my brakes with brake cleaner and see if that helps. Im also going to manually calculate my fuel mileage because this is starting to kill me.

 

I was just gonna say check out your brakes. It's amazing how a stuck piston can destroy mileage. However the 1/4 inch restriction at the muffler can cause a back pressure bubble that may be screwing with your O2 sensor which would also cause a drop in mileage.

 

The truck coasts freely so I'm guessing the brakes are fine. You think the restriction could be doing it? I'm going to fill up and drive around and hand calculate....see if maybe the gague is off. If it is the dynomax is there anything that could help that other than a new muffler? What about removing the resonator?