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What is your best MPG?

9K views 93 replies 65 participants last post by  Truevalue1 
#1 · (Edited)
I am just trying to see what some of you guys are seeing for MPG? If you have a DPF delete, EGR delete, module, exhaust, or just stock. If you knnow what your MPG was before and after improvements is can you post it? I want to see what combo is the best and if there is any normal result. Thanks.:popcorn:

Also, how many miles do you have on your truck?
 
#2 ·
The best I ever saw was 16.7 on a trip of 250 all highway miles between Ridgecrest and Vegas...3/4 of which was on I-15 through the two passes. Truck was completely stock, I did have a tailgate spoiler on it. Mileage was hand calced.

Since then I've made some suspension mods and added 35s. In town, my mileage dropped about 1-1.5 mpg. On the highway I still get 16.
 
#5 ·
I have right at 18,000 on the clock and I have averaged as high as 18.3 hand calculated on the highway but 16.5 is more the norm. Pulling it usually drops to about 11.5-12. I plan on doing a DPF and EGR delete soon!
 
#7 ·
We just bought 4 new 6.7's for work and they vary from about 14 to 19. They are totally bone stock and the most miles is about 12000. None of them get drove hard at all. Company vehicles.
 
G
#8 ·
Pulled out the baffle in the intake tube friday night. (Other than that, STOCK). Sat. drove 70 miles with a good 20 to 30 mph wind at my back. 18.9 mpg according to the computer. Coming back against that same wind 15.5 mpg according to the computer. Had the cruise at 63 going, and ran between 65 and 70 back. That is the best I've ever seen, and think pulling out that baffle might actually help a little.
 
#9 ·
With the mods that I have now, I'm seeing 20 - 20.6mpg (70mph hwy) hand calculated. The OHC reads 21.8, but like I said by hand its normally 20 on the hwy. I get around 11-12.2 while pulling a 11,400lb trailer.

Before I did the DPF delete and EGR, Edge ect, I was at best 15mpg hwy and 8 while towing.

I filled up my truck the other day and took a 400 mile trip and my tripmeter is at 470 miles since fill up, and I still have a 1/4 tank of fuel left.
 
#10 ·
Diver-thats great news. Can't wait to start gettin this 6.7 running like she should! I have a question for you, did you have any clearance issues witht he front mag-hytech diff cover? I just ordered the rear cause i heard sometimes the front doesn't clear properly. Any issues for you.

Thanks.
 
#14 ·
As my truck sits my Overhead reads 22 MPG, usually hand calculating it i usually see right about 17 MPG but that is without any long highway runs. I should have some updated numbers after this next weekend as i am going on a long trip.
 
#15 ·
Wildhorse,

Yea actually the front diff cover is tight. I'm not actually sure if it happened during the install, or if it happened while off roading, but my front cover is scraped. Here's a picture: You'll love the Mag-Hytechs, fluid change is a breeze and its zero mess on the garage floor. My rear end runs about 10 degree cooler than stock and they look sharp too.

 
#17 ·
Mine is stock still minus intake baffle and the bottom of the air box cut out. The best mileage I've seen was a trip back from CO. From Lakeview, OR (5000 ft alt) to Medford, OR (1500 ft alt) I got hand calculated 21.9 mpg. That was driving 65mph with the cruise. There are 3 pretty good mountains to cross, but other than that it's all down hill. Just took a trip to Portland and back and averaged 18.5, that was 70 mph on the way up and 75 on the way home.
 
#19 · (Edited)
This is my 1st post on this subject, but my 08 with the dpf delete, edge, & mega cannon has only shown a best of 17.5 on the overhead running @ 62. When truck was bone stock the OH would read 15.5 at the same speed. If I were to do it all over again I would have left it stock after spending close to 2 grand to gain so little doesn't make much sense.
 
#23 ·
My best was on a trip from Tx to SC 19.9mpg hand calculated the truck was bone stock and had about 7k on the clock now my best is 15mpg with the 35's :w: and 23k on it so far
 
#26 ·
Bobtailed

If I am bobtailing, I only get 12.5 average (hand calc.) if I am pulling my 12,000lbs. 5th wheel, I get 8.1. I am really beginning to despise this truck. I have the DPF and EGR deletes on their way. I am sure hoping that this will help.
 
#27 ·
If I am bobtailing, I only get 12.5 average (hand calc.) if I am pulling my 12,000lbs. 5th wheel, I get 8.1. I am really beginning to despise this truck. I have the DPF and EGR deletes on their way. I am sure hoping that this will help.

Your fuel economy will go up for sure with the dpf delete kit. The other day I averaged just over 13 mpg US pulling 12,000 lbs 5th wheel flat deck trailer.
 
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