As stated,

my 05 has 185K mles on it as we speak, and has just dropped within the last month from 15-16 mpg in the city, to 12.5-13.0 AT BEST.. highway is no improvement either, im gettin 16-17 highway hand calculated..

only mods to the vehicle are 5 inch exhaust, smarty S06 on level 5, and a drop in AFE filter..

i have already re loaded the smarty, recalibrated the speedo for 33 inch tires, ran it stock, ran it with smarty NO IMPROVEMENT AT ALL even with the smarty, but drivability is much better.... changed the fuel filter on it, and, theoretically.. im out of ideas..

any explanations? or ideas?

thanks

Rick

 

Check the simple things first, like air filter, tire pressure, and brake drag.

 

air filter is clean

tire pressure is optimum for my setting, 65 front and 60 rear, and brakes were just done, new pads, proper adjustment, discs resurfaced and so forth..

also, fuel is always from same station, so thats a constant as well..

 

How bout wearables like u joints, carrier bearing wearing down, or other attributes that could lead to more binding or resistance on the road???

 

Don't consider the same station for buying fuel as a constant. I worked in that industry and know unless there is a depot within reasonable driving distance, fuel is bought from the spot market. This is a common place where all refineries can sell their fuel if not in the area and has excess, or has station contracts for their stations in the area.

Like in the state I moved to, Tennessee. There are no refineries in the area and the companies pipelines are not here. But the common 'spot market' lines are everywhere and blending stations are used to receive the fuel, mix it to specs for the stations contract and deliver. Like the Shell and Chevron stations. They must meet minimum federal and state specs, plus companies contract specs, but you don't know who cut the base blend stock or blended.

Try another station for a couple of tanks to see if this can be an issue. But if it's their tank, and they are a high volume dealer, this is turn every three or four days with a new load to replace low levels for sale.

With diesel, there is minor changes from station to station on specs, it's usually a constant except for the difference in grade 1 or 2. Gasoline is a different story.

 

If everything checks out, and this is one of those "all of a sudden" issues, I would treat the fuel with some additives immediately. You probably have some type of contamination, whether it's water, bad fuel, particulate matter, or even algae.

I would suggest some Power Service, FPPF, and an anti-algae treatment specifically made for diesel/bio-diesel.




Kris

 

already adding stanadyne to see if it cleans out anything

thanks for suggestions guys

 

You're not "making oil" are you, meaning a leaking injector? Have you checked your engine oil level?

 

Time for a Valve Adjustment....

 

not yet,

ill do it soon as i get up for work

and valve adjustment, yup, i agree

 

Maybe you filled up with a tank of light fuel (#2 or heating fuel). Northern latitudes are blending to winter fuel with a 10-20% loss of power and economy.Perhaps your filling station received a tanker load by accident. However, does your truck display any of the following symptoms ;loss of power, black or white smoke from exhaust, heavy blow by from oil filler cap when the engine is cycled, any liquid leaking from your exhaust?? These could relate to a piston or liner scuffed. This also could mean a pre-existing condition in which your coverage will be denied. You have the right to appeal this decision but our decision is final. Also, check the air box for winter condo critters too. There might be a critter running that turbo.

 

i doubt it was heating fuel..

but to answer your questions..

no loss of power

light grey puff at start up

no blowby, clean undercarraige, no oil leaks..

no liquid leaks from exhaust..

i thought i had a very light haze from smarty, but after observing for a lil while yesterday, and right now.. nothing...

oil level is unfair, i park truck on a slight incline so i need to check it where im parked flatt..

 

According to Haynes your vibration dampner pulley may become detached from it's innercore. They are locked together by a rubber bond between them, and the rubber may fracture causing slippage which will cause retarded timing which would give you the poor fuel economy. Very easy to check and it will be fooling your timing sensor if proven. Check out Hayne's tune-up 02-06.

 

Looking for any updates or current info on this topic....I went on a trip from Oregon to Montana last week and my mileage went to heck. I pull a camping trailer and usually will 18 to 20 pulling...I got 13-14 this trip. Seemed to have plenty of power, was running a little hot - I could overtemp in 6th gear, where I typically can't - have to down shift to 5th on a big hill and then I'll see egt climb to 1300. But this trip I was having to watch it in 6th gear. Also seemed like it was running a lot o boost - even on flat ground and down hill. based on that, I was thinking I had a brake dragging or driveline issue - but I've checked all those mechanical things out and they are all good. Any thoughts ??

Thanks,
Rob

 

106,600 miles by the way...