black_z71_2wd

Hey everyone,

I'm new to the forum but have been a long time chevy fan, I drove my tahoe for9 years before I bought my 08 silverado 15005.3L v8 and had a few questions. I've been looking for suggestions on how to increase my gas mileage. So far the only suggestions have come from the guys in the pit at the oil change places. My question is would a cold-air intake and dual exhaust system increase my mpg? I'd like to hear testimonialsfrom someone who has made these mods to their own pickup.

I've done the research on wikipedia, K&N, flowmasters and other various websites but would like a first hand testimonial.

Thanks,
Sean

speedy58

as far as the exh and air intake
i gained 2 MPG with just the exh.
and .8 with the intake
and i got better times down the track
so i seen deff inpovemet in MPG, HP, and torque.

black_z71_2wd

Awesome, I'm def considering making these additions to my pickup , thanks for the input.

obfirefighter22

Ive got an 07 crew cab with a 6 inch lift on 35's...so yeah mine doesnt get that good of gas millege. Not sure if my dual straights or cold air intake help much, but i can say my hypertech II does seem to help my gas drinker of a truck. With my heavy for i believe i get about 12 miles to the gallon and around 13 if im ok on the pedal.

This is a topic im interested in to, cause i know im getting raped on gas. i need some good ideas aswell

87Moose

I have a cold air intake on my truck and yes it does improve gas mileage!

About the exhaust: Flowmasters are what you call "restricted mufflers" on theinside they look like this /\/\/\/\/\ Which restricts the air. On the other hand; a MAGNAFLOW is unrestricted looking like this ======== allowing for better flow, thus better performance.

Keep your tires inflated properly, because it reduces drag increasing gas mileage AND reducing tire wear.

Avoid too many "Sprints" in your truck. A slow and steady start and stop will greatly increase your gas mileage. I used to be a speed demon and was getting around 10-12 MPG but just slowing down has increased it to 15-18!

87Moose

Also, running cleaners such as; Lucas Fuel Injector Cleaner, or my personal favorite 104+ will clean out your lines which also increases MPG

sbroadus

I put two bottles of STP gas cleaner in every tank of gas and I have seen better gas milage every fillup.it is also a good idea to invest in exhaust and an intake system it helps in the long run alot

ukrkoz

1. your mileage will slowly improve around 70K miles, when engine breaks in
2. no, i did not have cold air intake installed on my silvie, but i had K&N typhoon intake on my 04 CR-V. i have a mileage log on hand to prove that it dropped mpg by solid 10%. i, also, know that every car is different, so maybe other members have documented mileage improvement, not just "it feels like it's better". everyone's mileage is better summer time, when temps are high, gas is formulated differently, and there's no traffic. i had mileage logged twice a day for 1.5 year. all i know is simple physics of how ECM operates: O2 sensor monitors exhaust; more O2 into the system changes MAF and O2 sensor readings and tells ECM that engine is running lean; ECM changes injectors pattern, injecting more fuel into the system. CAIs are power mod, not mpg mod, it's a known fact. along with ice bagging engines or injecting methanol/water mix, etc.
3. pretty much, anything that makes fuel burn more efficiently (that's why fuel additives/cleaners help some) or engine run leaner, will improve your mpg. along with one bulletproof way - driving habits modification. i, personally, can make only one suggestion that i know proven to work (as you already bought gas guzzler, so let's deal with the fact): HALO spark plugs. they are proven by independent research and by research done by Ontario government to improve gas mileage. also, you could twik transmission towards fuel economy shifts. and yes, they can be purchased in any OEM heat range specification (and i have 2 trucks running on them for long time with no adverse effects).
base line is - those trucks were never ever marketed as fuel savers. they are workhorses, and like any workhorse, they got to be fed, and fed well.
here's link for you:
http://peswiki.com/energy/Directory:Fuel_Efficiency
those guys have tried EVERYTHING possible to improve mpg. show me at least one place where it says that CAIs improve mpg. belly pans do. aerodynamic mods do. acetone has no effect on silvie, i tried.

fromdodge2chevy

a gas engine finally breaks in at 70k miles? no way!!!!! at 70k a gas engine is approaching midlife, depending on how they are maintained.gas engines aren't in the same league with diesels. dieselsfar outlast gas engines. dieselsbreak in at around 10 to 20k, depending on how they are used. its ridiculous to say a gas engine finally breaks in at 70k miles. secondly, if you allow the engine to breathe easier, ie. freer flowing intake and exhaust, it will cause the gas mileage to go down. the engine management computer will sense more oxygen entering the engine, the computer compensates for this extra oxygen by adding more fuel to the mix. if a gas engine runs lean on the fuel air mixture it will run hotter. the computer will not allow this to happen via control of the fuel injectors. aftermarket intakes and exhaust systems may make your truck run a little faster, but will not help gas mileage.

sbroadus

you could also try a tuner!!?