6.0 Highway Fuel Economy

[720Deere]

I just wanted to share my fuel economy results from my trip to Scuffy's and back home via Myrtle Beach. On the way down running my IDP Street tune I achieved 19.9 as long as I kept it under 68 mph. Once I increased speed to as much as 72-73 the average dropped to 19.5 mpg so I can only assume that I was seeing about 1 mpg less. After the headstuds were done (big thanks to Scuffy for that one! ) I headed down to Myrtle beach and averaged 20.3 mpg over 230 miles using the Xtreme Race tune and traveling 65-75 mph.

We drove home today with part of the 535 mile trip being in the rain and saw some peculiar results. Traveling at 80-83 mph I was seeing up to 21.8 mpg. If I drop the speed down to 75 or less mph the mpg drops like a rock. The race tune loves to see 2200-2300 rpm for maximum economy. I should have hooked up AE to keep an eye on the injector timing at certain rpm but I was way too tired to fool with that. My overall average today was 20.7 mpg over the entire 535 mile journey.

All of these figures are from the in-dash monitor. Before you bash me in the head with a baseball bat and inform me that the "lie-o-meter" is not accurate, let me tell you that mine has always been within a few tenths when I check it by hand. I consider the margin of error to be about 0.5 mpg just to be safe. At any rate, I was very surprised to see it gain mpg and not lose at speeds in excess of 80 mph.

Also to add to this, the truck weighed approximately 8500 lbs on the trip down and well over 9000 lbs on the trip home after I picked up the family at the beach. My best fuel economy was on the race tune carrying 500+ additional pounds and running 80+ mph. God I love the SCT!

[vitalidle]

Sweet! I wish I could see that kind of mileage. I think I need to change my tuneing!

[bluestroker]

very good mileage Matt so I guess your trip to see Scott was a success

[720Deere]

Winston-Salem trip was a huge success. I got to be a witness to 90% of the process and he only spent about 8.5 hours on the job. That guy moves like cat stalking it's prey! It really was a pleasure to watch him work. Besides as Scuffy would say, he looks good doing it too!

If anybody out there is within driving distance of Winston-Salem and is looking to get headstuds installed, you need to contact Scuffy828. I've been around a lot of "mechanics" in my lifetime but he is more like an artist! The most amazing thing is that everything is exactly where it was before the job and there was not a single nut bolt or washer left over when he was done.

[Lord Tauk]

Sweet MPGs!

Big Red is back, and hungry for some 1320!

[detroitdiesel64]

what are headstuds? sorry im new

[rednekexprez]

Thats great glad to hear it...I run the xtreme street as daily and my mileage went up quite a bit....

[720Deere]

Originally Posted by detroitdiesel64

what are headstuds? sorry im new

Headstuds are high strength studs used in place of the weak factory headbolts. The factory headbolts in a 6.0 are known to stretch leading to headgasket failure.

[JBakerFX4]

Sweet. I've been averaging 19.9 ish at 65 with my 4" lift and 35's. I've seen some similar results when cruising around 80 the MPG's can sometimes pick up and go to 20 or 21. when the RP's are 2,100-2,300. Very hard to find the sweet spot at those speeds. But I have seen better results at 80ish vs 70 with my stock tune mind you.

[eazenutz33]

xtreme street, 6" lift, 37's on 20's, and fuel filters ready to be changed.....last tank was 18.6mpg....down from the previous check at 19.2.
Fuel Filters are in the back seat waiting for my lazy butt to change em...hopefully it will go back up, but I'll still be praising SCT via Eric from the rooftop!!!!

At 70ish my truck is running around 1400-1600rpm and almost sounds like it isnt even running....to pass people it feels like it changes "stages" and thrust forward without downshifting, may get a lil burp of black smoke. ROMP on it at those speeds and I get a nice "ploom-o-coal", a silky smooth downshift, and a violent thrust forward.

Compare to my buddy's 05 with an 8" lift, 37's on 24's and a new Edge Juice with Attiditude,.....best mpg was 11.5 according to him complaining. His coolant blows everywhere from JUST DRIVING, and his truck shifts horribly and violently....he was complaining he may need a kidney belt to drive!

Think we may have another SCT convert!!!! hahaha