rookie mpg question

Its more like 0100...

 

It shouldn't be that hard to get 8mpg.. tool around all week @55-57mph just to maybe get 8 or fall short quite often? Truck is broken.

I think there is a problem/conflict with the QC and/or OnGuard that derates the motor. I'm fighting with it also.

When I first got this truck I could run 62-65mph all the time and hit the hills hard for 8.4-8.6 weekly averages. It had power and was easy to drive, the motor was responsive and shifted like a dream. Now it lags and shifting isn't as smooth, it's gutless, and standing on the throttle to merge on the highway at 35mph is stressful.

The truck I was in before this did the same thing and I've spent way too much time in the shops for nothing. The problem isn't obvious so it's not something they want to deal with, They will just make up some garbage to tell you to get you "fixed" and out the door.

I've been talking to the wrong people.

 

At some point you do have to get the overhead done ya know...

 

That will help as much as adding some of those snake oil additives to the fuel.

There is something else going on.

 

Setting alll the basic mechanical adjustments in the top of the engine is snake oil???? Please!!!! Its step number one in getting a poorly performing diesel back to great operating condition.

 

Mine is due for overhead. Shop says the mpg will drop initially after that but then improve.

 

I think it is more of a software problem so an overhead won't help much. The shop guys don't want anything to do with problems that aren't obvious so it's like pulling teeth talking to them.

 

Two questions...what do you have, and has the overhead ever been set?

 

15 Cascadia and it is due for an overhead. Had it done on a 12 and it didn't help, it also had two sets of injectors replaced but it did get some power back for a brief time on the second set. It's its more like a loose wire somewhere.

 

People with pacarr motors have the same or simmilar issues, low power and poor fuel mileage, so I think it could be something that they both have in common like the QC, or collision avoidance, stability controll that is malfunctioning and derateing the motor.

I've noticed it is intermittent but the more time passes the longer it goes without power.