Diesel guys please help!

redneckcj5guy said:
(Not a thread jack but...)
Mine is a 2008 lmm CC DRW.
Hand calculated mpg is 12 unloaded....
8 mpg @ 24000# loaded.
So why does it suck so much fuel unloaded?
Bone stock, 60,000 miles and one owner.
Take me to school folks!
I wanna know about dpf delete and such.
Click to expand...

Dpf and egr delete will increase your mileage a good bit.

Sent from my DROID BIONIC using Tapatalk
 
mysterync said:
Dpf and eye delete will increase your mileage a good bit.

Sent from my DROID BIONIC using Tapatalk
Click to expand...
eye delete?
Please explain sir.
 
I'm betting that was supposed to be "EGR delete"... and his phone's autocorrect 'fixed' it for him.

You can try an eye delete, but it'll just mess up your depth perception.
 
every dmax i've seen gets better mileage with a hotter tune. Hotter tune doesn't meat beat the shit out of it and get great mileage but you will see a difference. Emissions equipment will plug it up some and drop your mileage. If you haven't purchased a tuner i advise getting EFI Live and a well reputable tuner and you can find those on various dmax websites. Rob tuned mine and it was great. Very good driveability and great MPGs. 500hp was a good thing too.
 
Hurley said:
^the OP states that he has the ppe tuner set on 160 (is that 'kill' or 'piston melter' tune?)
Click to expand...

Lol nah a factory lly will tow with the "425 hot plus 2 et " just fine...wont hurt a thing.... least that's what I heard

Sent from my DROID BIONIC using Tapatalk
 
Shawn said:
Did the 04.5 trucks still have problems with leaky injectors? How about a sticky brake caliper?
Click to expand...
The LLYs weren't nearly prone to the injector problems as the LB7, but as with any diesel (or any fuel injector for that matter), it is a possibility. They did however suffer from wiring issues on the injector problem that could be linked to this issue, though generally drivability would noticeably suffer as well.

Hurley said:
^the OP states that he has the ppe tuner set on 160 (is that 'kill' or 'piston melter' tune?)
Click to expand...
It would take more than the 160 tune to melt pistons, unless you were using it with stock exhaust and towing heavy.

The 250 PPE tune netted a best of 25mpg (the DIC in the dash was saying nearly 40mpg :lol:) but I usually got 21-22 with normal driving.


A few more questions, you never stated if you have oversize tires and if you are compensating for that? You could be traveling up to 15% further than the ODO says, if say you happened to be running 35s. Although with the PPE you should have corrected that while loading the tune.

Since you are running the 160 tune, I would turn the boost controller up a little to make use of the extra fuel, drop EGTs and probably get a little better mileage, especially if you have any noticeable smoke while driving.

Also, what kind of driving do you do? Your truck doesn't like going over 2000rpm on the highway for fuel mileage, which pretty much limits you to 65 mph depending on tire size. I know there was an easy 2-3 mpg drop between 60mph drives and 75mph drives on the interstate on my truck.

If you still have the Cat, it is likely it could be clogged running the 160 tune with the boost controller turned down.

14mpg isn't "horrible" but not good either. Keep in mind, the LLY, LBZ, LMM, LML RARELY get LB7 mileage numbers, so don't be comparing it against a 01-04 truck.
 
Yes I have ran higher tunes. I just have ppe standard so I can only go up to 220. I keep it on 160 though and I do keep my foot out of it. I did try 220 but it seemed slightly worse. I keep it at 2,000 on the highway and my speedo is dead nuts according to a couple of gps units I have tested it to. I put my stock intake back on and it seems to be getting a little better. Not sure why I thought more air in more air out the better, but i have heard on afe messing with mpg with wet filters. I am going to fill back up and run a whole tank with the stock intake back on and see what happens. When I tow my jeep on just a car trailer there doesn't seem to be much difference in mpg. I still get just a little under 280. That not that much difference when im unloaded.
 
redneckcj5guy said:
(Not a thread jack but...)
Mine is a 2008 lmm CC DRW.
Hand calculated mpg is 12 unloaded....
8 mpg @ 24000# loaded.
So why does it suck so much fuel unloaded?
Bone stock, 60,000 miles and one owner.
Take me to school folks!
I wanna know about dpf delete and such.
Click to expand...

I have a LMM also. DPF delete, K&N Intake and 4" turbo back exhaust, empty 15.5 to 20 mpg, loaded with 32' 5th wheel 12.5 mpg as long as I keep it around 65. Shoot me a PM to discuss it further
 
thats terrible mileage for a dmax,I have a 2002,with 550 hp at rear wheels,and i get 19-21 hwy all day,i have several friends that have same trucks and they get same mileage,I would think it would be your injectors,but it is hard to diagnose without hooking to tech 2 scanner,Eds Diesel Performace,in Landis NC does all the work on mine,hes is very knowledgeable about duramx,I would suggest looking him up,
 
Im a little late on posting but i thought i would ask. When you did the egr delete did you do the finger sticks? If not that could be a problem. I dont think the ppe programmer completely deletes the codes in the ecm or if it does anything for the egr delete at all. Not sure if it helps but its something to look into.
 
Back
Top