Last post on Mar 27, 2013 at 11:39 AM
You are in the Chevrolet Silverado & GMC Sierra
What is this discussion about?
Chevrolet Silverado 1500, Chevrolet Silverado 2500, Chevrolet Silverado 3500, GMC Sierra 1500, GMC Sierra 2500, GMC Sierra 3500, Fuel Efficiency (MPG), Truck
#125 of 176 Re: The Answer To Question One [nitrous05]
Nov 24, 2010 (1:48 am)
actually the turbo efficiency idea is not that it makes more power ]to move the truck easier. This is because when you see the highest mileage with the turbo you're not going to be under boost. What makes it more efficient is the slightly greater volume of air coming in at lower rpms vs. stock. This leans out the air/fuel mixture (which is usually corrected for in the tune), and the higher volume of air is what allows for a turbo engine to create a more dense air/fuel charge.
for example if your car got 20 mpg, you add a turbo and no intercooler, you would be lucky to see 15mpg. So you can see it isn't the turbo or the extra power, it's simply the extra air coming in while under vacuum (not boost). What you do with that air in terms of cooling and tuning is what generates the extra efficiency.
#126 of 176 Re: Chevy Truck Gas Mielage [hutch54]
Nov 24, 2010 (2:33 am)
hutch, your 4x4 suburban does not get 24 mpg on the highway.
The best mileaged 4x4 suburban is the new 5.3L 4x4 with 3.08's and the double overdrive, on the highway it gets 21mpg, 22 is great driving, 23 is stretching the truth but perhaps possible, 24 is bullshit. The 2wd tahoe hybrids don't get much more than 22 hwy. Fullsize 2wd pickups with the 5.3 and 6speed get at best 22mpg. S10 4.3L's with the same 3.08's get 26mpg at best. you are full of shit.
#127 of 176 Re: Chevy Truck Gas Mielage [hutch54]
Dec 11, 2010 (2:16 pm)
I also agree there is no way you can get 23-24 mpg with a 4x4 suburban!!
I also don't think your brother gets 12 mpg with his 1/2 ton ford unless he runs the nuts off of it, seeing as mine gets 18 mpg!
#128 of 176 Chevy Truck Gas Mielage
Dec 17, 2010 (7:23 pm)
well i have a 07 chevy silverado, crew cab with the 5.3, im getting 12-13 mpg, i actully just took it to the dealer today and they say its fine ugh how do u get better mpg out of these trucks, this is rediculas!!!
#129 of 176 Old for New
Dec 18, 2010 (9:07 pm)
Hi all, I'm trading in a 2000 Silverado Ext Cab with the older 5.3L V8 that would easily get 21 to 22 MPG highway driving (though my wife got 24 MPG once or twice, no tailwind either!) for a new 2011 Silverado 5.3L Crew Cab.
I attribute most of the over 20 MPG rating to a hard bed cover. It was a 4 piece folding cover that I loved. I plan to get the 3 piece cover that GM offers via the dealerships, but in a few months after I swallow the Tag/Title/Tax costs first.
#130 of 176 Re: 08 silverado losing gas mileage [maybe1]
Mar 01, 2011 (2:04 pm)
Im having the same problem did you ever get it figured out?
im only geting 11 mpg in town and 13-14 on highway. they say nothing is wrong.
#131 of 176 Re: 08 silverado lost gas mileage
Mar 05, 2011 (7:42 am)
My 2008 silverado used to get 18.5MPG HWY, and 13.5MPG city, but now I get 11.5MPG city, and 15.5MPG HWY. Took to dealer and they were no help, said could find no problems with truck, I think we got a big lemon! The only reason I bought this truck was because of the better MPG, I'll never buy a Chevy ever again unless this porblem can be fixed?
#132 of 176 Re: 08 silverado losing gas mileage [travelcheve]
Mar 15, 2011 (10:33 am)
The best fuel economy possible is the direct result of proper maintenance and good driving habits. Listed below are GM's recommendations to achieve the best mileage possible. The first group are things to consider for your vehicle, while the second are tips relating to your driving habits.
One of the major contributors to poor fuel economy are under inflated tires. Tires low with pressure create drag that the vehicle’s powertrain must overcome, wasting dollars in fuel. Always keep your tires inflated to the proper pressure as shown on the vehicle placard. This not only serves to increase gas mileage but cuts down on tire wear, further decreasing your costs per mile.
A vehicle that has a dirty air filter can’t efficiently draw air into the engine. This restriction forces the engine to expend energy to "breathe" wasting fuel in the process. Change recommendations are found in your vehicle Owner’s Manual.
Always use the proper viscosity oil in your engine. Oil that has a higher than required viscosity will create more drag on the internal components of the engine causing more work for it, especially when cold. Each Owner’s Manual contains information on the proper type of oil for your vehicle. Look for the "starburst" symbol on the front of the bottle, and the SM rating on the API circle on the back label. If you are in doubt, stop by your dealer for an oil change, and any other services required. Most current GM vehicles are equipped with oil life monitors to further assist on the "when" to change your oil. (Aveo/Wave/Optra/Epica currently do not have oil life monitors).
Note: GM Vehicles DO NOT require additional engine oil additives. Some additives may cause harmful effects to the internal seals and additionally void the terms of your vehicles New Car Warranty.
Purchasing higher than required octane fuel is a waste of money. Using higher octane fuels in a vehicle that only required regular unleaded fuel will neither increase performance nor improve gas mileage. In all cases refer to your owner’s manual and ONLY use the octane rated fuel recommended for your vehicle.
Even though current GM vehicles have 100,000 mi (160,000 km) service intervals for spark plugs if your vehicle is at that point in its life, have the spark plugs changed to assure proper running and continued efficient, trouble free operation.
Avoid quick/full throttle acceleration from a standstill in town and high cruising speeds on the interstates. While the optimum MPG for highway cruising speed varies from vehicle to vehicle, faster is almost always worse. If your vehicle is equipped with a Driver Information Center that displays Instant Fuel Economy, select that readout and vary your cruising speed while on the highway. The display will change continuously with uphill and downhill sections but you should quickly be able to identify on level ground the speed range that your vehicle does the best in. Avoid leaving unnecessary items in your trunk. It takes power to move increased weight and that means more gasoline consumption and reduced performance. While the change may be slight, multiplied by thousands of miles, it all adds up. Your vehicle uses much more fuel when the engine is cold. This is especially true in the winter months when the engine will take the longest to warm up. Combine errands or trips so that the vehicle only needs to warm up once to encompass many different stops.
Please also feel free to get a second opinion from a different dealer.
GM Customer Service
#133 of 176 Re: 08 silverado lost gas mileage [aaroncorpus]
Mar 17, 2011 (6:00 am)
I would recommend having your vehicle looked at by an authorized GM Dealer. I would also recommend reading post #132, as there are some helpful tips. Please keep me updated as to what the dealer says.
GM Customer Service
#134 of 176 New GMC SLT 4x4 Ext Cab Z71
Mar 18, 2011 (6:54 am)
I’ve own a lot of trucks over the years. Until recently the last one was more than a dozen years ago. I got fed up with the drive quality, the fuel economy etc. Recently purchased a GM Sierra SLT, absolutely fully loaded. It does have the latest in electronic technology such as phone (bluetooth), Sat radio etc but GM has done nothing to address the fuel economy. My Sierra has the all aluminum engine, 6 speed transmission, active fuel management (YAWN) and a list a mile long of features but really, it means nothing if the GD truck farts gas by the gallon. I recently did a round trip of about four thousand miles and averaged 14.7 mpg. Granted I had an ATV in the dump but my speed was consistent at 55-60 mph. Around town with nothing in the dump, I get about 12 mpg. I guess in 12 years nothing but the shiny stuff has really changed with GM or the other domestics. I realize now why I gave up trucks all those years ago and went offshore. It is cheaper to rent one if you need it and have a quality buildt foreign with a tow hitch. The trailers today are mostly all aluminum and are light, so tow capacity is not so much an issue anymore. Anyone want to buy a truck?
Who combines errands to save gas? Vehicles are meant to be driven and in the years since my last truck, I’ve not had to consider fuel economy. My point being, GM has done nothing to address the problem as the same directions were given to people years ago by GM to reduce gas consumption. We should be given a gas rebate every year by GM IMO. That or put a light weight diesel under the hood for those of us who’ve spent $50k on a new truck. Good luck to you all.