So, my truck as about 11,200 miles on it. I just pulled a Blackstone report on the truck with the last oil change and saw that I have 3% oil dilution. As well, this truck gets between 1.5 and 2 mpg less than my 2011 F-350.





Any thoughts here? I've see highway fuel economy as low as 13.5 mpg as an average. As well, this truck religiously says I've used less fuel than I pump into the tank at each fuel up. I have all of the fuel records in a notebook.


A new Duramax will cost me 7 grand to switch, but I'm tired of getting mileage that a gasser truck would get, but don't know what to do.

 

you drive a bunch of city stop and go? Idle a lot with this truck? How many hours are on the motor?


do you know your regen interval?


Is your tail pipe clean?

 

Engine Hours: 274
Idle Hours: 39
Mileage: 11,200

Over half this oil change was a trip to CO Springs and back. The rest was in / around Las Vegas area with very little city driving. I commute in my car mostly and the truck sits.


Regen between 2-3 times per tank....its easily less than every 200 miles. Exhaust pipe is still shinny Chrome.

 

So if you are regening 2-3 times per tank. What is the mileage interval?


This sounds to me like something is not right with fuel trims.

 

That's what it seems like to me, but how do we prove it? Interval is less than every half tank. Over 2 tanks of fuel, I'll easily see 4-5 regens, but I don't write down each event.

 

I don't know much about the Duramax mileage but if the GM is known for great mileage and makes you happy, 7 grand may be another year of payments. Not too much if the Ford is not making you happy and it cannot be fixed by your dealer.

 

Yeah, its a year of payments. Its not the end of the world, but I'd rather keep 7k in my pocket and make Ford fix my truck. I still very much like this truck, but I don't know how to convince Ford to take it seriously. Also, who's to say I buy that Denali and then have problems with it?


I can't say I've exhausted all of my Ford options. If I had, then I'd just switch. I haven't contacted Crystal yet either, but then again, I don't know if I have enough information outside of my log book of fuel stops and this oil report. I do know that at the last oil change, they drove my truck 20 miles with a computer hooked up and got 17.0 according to their printout. I will also say this truck hasn't averaged 17.0 on the highway in a long long time, but I do know that my 2011 would easily get over 18-19 out here driving the same way.


No Crystal ball....

 

keep a log and show them fuel receipts and the log book.


What about boost? Higher than normal based upon the route you drive?


I had that happen on my 08. I told them my fuel ecomony was down and I was pushing higher boost than normal.


My high pressure turbo was out of spec so they replaced it.

 

Hmm. I don't think I'm running more boost than normal, but its tough to say. I run about 10 psi (1st tick) when running down the road at 70 mph. Maybe a hair less on complete level ground.


It seems like I need more data.

 

Boost is (to me) a tad high. I only run 5 or less on flat ground running 70. Stock tires? Someone maybe play a trick and lock your hubs?

 

Keep the ideas coming! I need to be talked off the ledge!

Hubs are not locked and haven't been. 4x4 system seems to engage / disengage properly when I've used it. The tires are the stock 20 inch rims.

Nothing is aftermarket on this truck outside of new shocks and a steering stabilizer. Heck, even the Tonneau cover says Ford on it !

I do run the Ford Cetane booster in the truck too. No aftermarket stuff there either (forgot to mention that).

 

I've read several reports from '15 owners complaining about fuel economy compared to their previous 6.7 PSD. Having said that I also haven't read where they got this fixed either.



Also you may try turning off your trailer sway control.








Good luck...

 

Pressure sensor on the DPF? Bad exhaust sensor?

 

If that freaks you out then maybe mine will make you feel better.
It idled a lot on the first batch of oil but it's still concerning.

 

Are you getting poor fuel economy too? I'm concerned between my poor fuel economy and the higher than average fuel in the oil. I changed this oil early too...