chevy 6.0 gas mileage

[sleekster]

so i have had my 2004 silverado 2500 4x4 crew cab with the 6.0 litre now for 15000 miles and my gas mileage is 10 in the city and the best i ever got on the freeway is 15mpg. this just sucks. i love the truck but the gas is becomeing a real issue. anyone have any experience installing say an aftermarket air intake/filter and or a cat back exhaust did these modifications help gas mileage? or what have you done to improve gas mileage? hate to throw good money after bad.

[PerfectionDtail]

I had an 03 2500HD 6L and I just traded it in on a 04 Duramax 5 days ago.
On the 6L, I added a Pro Cold Air Intake by Pro Dyno (www.prodyno.com) and a magna flow exhaust. There was little, if any, change in mileage, but it did dyno at about 340 HP.
If you are trying to get better mileage, just leave it alone, but if you want more power, I liked my setup.

[sigepmock]

I have a 2003 2500hd crew cab 4x4 with the 6.0L. Before I put the supercharger on I did the K&N FIP Kit, Flowmaster exhaust(catback), and the Hypertech programmer. I saw improved milage and power. I was averaging 13-14mpg. I have 4.10 gears and 285/75R16 tires. You should just put the Whipple on it and then you won't have to worry about mpg.:p

[UnionJack]

Like they said before... buy a Duramax.... you will never buy gas again

[77charger]

I have a 4x4 also and it seems to get about 12.5 on avg.I think i can get 13.5 if i drive all highway and keep it under 70.I have 5300 miles on it now.I get about 10 towing the boat and about 9 towing my toyhauler 18ftr.I have the stock tires and the 4.10 gear ratio
So far i am happy with the truck and the job it does towing my toys around.Any heavier i would have gone with the 8.1 but this truck suits my needs just fine.

[LOWRIVER2]

I've got a 01 GMC 2500HD 2wd with the 285/75's. Mileage is 11-12 around town, 13 on hwy ( non towing) and that's if I feather the pedal. Either do the performance mods and have fun or buy a diesel, GM never said they were efficient engines. Check out pickuptrucks.com , they have good info. and the Wester's chip sounds like the one to go with for performance.
I'm going diesel in 06/ would go earlier if I did'nt have a co. take home car, that mileage is expensive these days.

[boxscore]

I've got the 6.0 and 4:10 gears....I get a little over 10. Worst of all I've got a crew cab short bed.... makes it a 26 gal tank.... I'm gassing every 2-4 days. The 8.1 and 3:73 gears gets better mileage from what Ive seen. Of course, with hindsight, I shouldn't have been the cheap bastard and went ahead and got the Dmax. I will own one soon.

[tool 'n' jet]

I had a 2001 HD Crew cab the worst gas mileage. I put a volant intake, cat back exhuast, power programed that thing still terribble. I sold that thing and bought a f350 with a 6.o diesel much better gas milege 15 to 16 on the highway about the same in town... Good luck...

[sigepmock]

Man that's some shitty milage. Even with the supercharger and driving in downtown LA traffic I am still getting 13mpg. Just came back from Havasu on Saturday, not towing, with the cruise set at 75 and I got almost 14. I even checked the speedo with the GPS, it's right on the money. 4.10's, 285/75R16's, Headers, Flowmaster exhaust, K&N FIPKit, and the Whipple S/C. Maybe I just got lucky.

[goneboatin]

I recently got rid of my '99 Silverado with the 5.3L; that thing got a constant 17.5 mpg on the road doing 80+ mph and about 13.5 towing ... and that was with 125,000 miles on the clock! But my kids outgrew the extra cab back seat and I bought an '04 2500 crew cab with the Quadrasteer option. Lemme tell you the Quadrasteer rocks! It's like driving a much smaller car when it comes to maneuvering in a parking lot. When backing up a trailer it's a little different because when you make a correction, it happens like right now. The only dark spot is the motor. I just doesn't have the huevos to justify the crappy mileage. I didn't think 40 more cubic inches would make such a difference in mileage. I put 20's on it and got a Hypertech programmer to calibrate the speedo, but it did nothing other than firm up the shift points. The mileage still sucks, but at 70 mph, it'll kick down to second and pull hard but it's almost at 5000 rpm. I guess next time I'll just bite the bullet and get the Duramax. Hopefully they'll offer the Quadrasteer option on it then.

[Raskal]

well iam glad to here that my crew cab 4x4 is gettin the same as the 4x2.i also got the intake and magnaflow and hypertech chip .the truck runs great the best i ever got was 15 mpg and that was towing the boat .then agin that was at 55 all the way on the way home from powell .she was following me the motor home and that wont do much over 55 . the rest off the time i only get 10 to 11 mpg an i drive it like a race car all the time .