My 2012 GMC Sierra
 

2012 GMC Sierra Ext Cab SLE
Vortec 5.3L SFI Engine
6-Speed Auto Transmission
Summit White w/Ebony

Re: My 2012 GMC Sierra
 

It is equipped with:

POWER TECH PACKAGE
VORTEC 5.3L V8 ENGINE
W/ACTIVE FUEL MANAGEMENT
6-SPEED AUTOMATIC TRANSMISSION
LOCKING REAR DIFFERENTIAL
TRAILERING PACKAGE
ALUMINUM WHEELS
HEAVY DUTY COOLING
AUTO DUAL ZONE AC
BLUETOOTH FOR PHONE
CD PLAYER WITH USB PORT
STEERING WHEEL RADIO CONTROLS
PWR SEAT ADJUSTER - DRIVER
6 WAY
FOG LAMPS
LOCKING TAILGATE
EZ-LIFT TAILGATE

CONVENIENCE PACKAGE INCL:
UNIVERSAL HOME REMOTE
ADJUSTABLE POWER PEDALS
REMOTE VEHICLE STARTER SYSTEM
REAR PARKING ASSIST

ON THE JOB PACKAGE
SKID RESISTANT BED LINERS
BED RAIL PROTECTORS
BED MOUNTED TIE DOWN HOOKS

POWER REAR SLIDING WINDOW
INTEGRATED TRAILER BRAKE CONTROLLER
17" ON-OFF ROAD BW TIRES
REAR AXLE, 3.42 RATIO
7,000 LBS GVWR

OFF-ROAD SUSPENSION PKG INCL:
OFF-ROAD SKID PLATES
HIGH CAPACITY AIR CLEANER

Re: My 2012 GMC Sierra
 

looks great... i just bought one yesterday .. 2012... extendedcab as well. i like the 5.3 and 6speed.. nice truck

Re: My 2012 GMC Sierra
 

When I bought my 2011 GMC, I found that the 93 MPH cutoff had to go. I now have changed that to a point that it does not interfere with the operation of the truck. The 5.3, with a six speed tranny is a good mix. A set of headers awakens the monster in the engine. Mine is a standard cab truck.

Re: My 2012 GMC Sierra
 

Hey thanks. The truck has plenty of power for me and I am getting use to the 6 speed. I bothers me some times how it downs shifts. I have 1,400 miles so far and I like the truck but I hope the millage improves. I am only averaging 13.8 MPG :devil:

I'm only adding a few bolt on items to the truck. Vent visors, oval tubes, mudflaps, under seat storage tray, and I just ordered a Rough Country 2" leveling kit for the front ;) Nate

Re: My 2012 GMC Sierra
 

I get 19 MPG average with my 2011 2wd SWB, but your 4wd will affect that some. I had the 6 speed shift points modified when I did my computer tune. I did not like the overlap sensation from the downshifts and I wanted it to shift faster than it did from the dealer. I really like the setup, now.

Re: My 2012 GMC Sierra
 

just ordered the under seat storage... nice!

Re: My 2012 GMC Sierra
 

I bought the Husky brand and it's a very nice piece ;) I just ordered the rear wheel well liners also :metal: I'm thinking about changing my door handles to the painted style.

Re: My 2012 GMC Sierra
 

Where did you guys get the under seat storage?

Re: My 2012 GMC Sierra
 

I bought mine on Ebay. Best price I could find ;) http://www.ebay.com/itm/09011-Husky-...item4604e64217 Nate

Re: My 2012 GMC Sierra
 

Here goes a before and after pics. First pic stock and second pic with a 2" Rough Country leveling kit installed. Also Lund oval step bars, rear inner wheel wells and side vent visors.

Re: My 2012 GMC Sierra
 

I like it. just ordered oval bars and bed liner for mine. Thanks for the pics. Nice truck.
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Re: My 2012 GMC Sierra
 

I'm averaging only 11.5mpg with my '13 GMC SEIRREA SLT. A ways off from the sticker of 17mpg. Considering Headers w/High Flow Cats. made a difference with my 2005 GTO, almost 2mpg and 28HP at wheels. Anyone in here know if this would be the same with the LQ block compared to my LS in the GTO?

Re: My 2012 GMC Sierra
 

11.5mpg? I'm getting 16mpg in my '12 with a 4.8 and 4spd. I thought the 5.3/6spd was supposed to be better.

Re: My 2012 GMC Sierra
 

Me too. Called GM Hot line. Phone idiot said wait until after break in. I asked what do you consider break in period. response was 5,000-7,500 miles. I said ok I guess I will just buy a gas station until then.......not to mention I would have ordered the 6.0 liter at that point.

Re: My 2012 GMC Sierra
 

My 5.3 in my 2011 started at 18 to 19 MPG and it is still in that area. Standard cab, SWB, 5.3, 6 speed auto, 3.42 gears with 20" rims. I did a EFI Live tune and put headers on, and the mileage is still around 19 MPG UNLESS it is really cold outside, then it drops.

Re: My 2012 GMC Sierra
 

I also have 3:42 gears which should be a + for gas mileage. The first two tanks I even eased my foot on the gas like the pedal was made from egg-shell. All my friends at the race track have 5.3's that they tow their enclosed trailers with. They tell me they are getting 11 with a trailer.......I sure hope there is something true about the break in period before gas mileage gets better or I will be regretting not going through with the deal on the FORD w/ECCOBOOST. Thanks for the input on your truck.

Re: My 2012 GMC Sierra
 

The Eco-boost isn't getting anything anywhere near what Ford is claiming. A friend has one and he's regretting shelling out the money for 15mpg. Sure he's got more power then my 4.8, but we tow the same thing, and I paid close to $15,000 less. And those turbos are going to be a fortune to repair when they go.

Re: My 2012 GMC Sierra
 

Yea....TURBO'S X2....ouch

Re: My 2012 GMC Sierra
 

I agree, the people that I know that purchased the Ford Ecoboost setup are really put out that their mileage is worse than mine. I have good gas mileage and plenty of power in my setup. I would really like a 3.73 gear, but it would curb my highway m,ileage too much. When we did the computer tune, we also closed up the shifts in the transmission computer. There is a lot of slop in the shifts and it allowed for too much tranny flare issues. in other words it would take too long to go from one gear to another.

Re: My 2012 GMC Sierra
 

Well I have about 4800 miles on the truck now. I am averaging 14.8 MPG city driving.

I don't have any plans on modifying the truck mechanically at this time. All my expendable money is being spent on my 67 :metal:

Re: My 2012 GMC Sierra
 

I can live with 14.8 but this 11 crap has to go......

Re: My 2012 GMC Sierra
 

I owned the exact same truck as you except it was 4 door and my millage never improved (never got over 15 mpg) I loved the truck though so I just got over it :lol:

Re: My 2012 GMC Sierra
 

Mine is a crew cab.....15mpg I would be ecstatic with :gmc2:

Re: My 2012 GMC Sierra
 

That Z71 package is killing you.

Re: My 2012 GMC Sierra
 

What package would get the best gas mileage then I'm about to buy a new truck 4 door GMC.

Re: My 2012 GMC Sierra
 

If you can, wait to see what the MPG is estimated at for the new trucks. They are already saying better then the current models. Best you're going to get is 18-20mpg with the current model, but thats in a reg. cab short box, with a 5.3/6l90e and a grandpa foot. In a crew cab you're going to be around 15-17mpg avg.

Re: My 2012 GMC Sierra
 

Also, what kind of driving do you do? In town, country, highway, a mix of two or all of those?

I bought the 4.8 with a 4 speed because it better suited my in town and country drives, I didn't need the 6 speed, and didn't care that the 4.8 is only 26hp less then the 5.3. I average 16-18mpg with stop and go, and 80km/h county driving. The 6 speed would spend most of the time changing gears needlessly in my case. Sure it would come in handy at 80-90km/h, but the 3.42's keep my rpms at about the same as what the 6 speed would be at, at those speeds.

Re: My 2012 GMC Sierra
 

I have a 2011GMC SWB, 5.3, 6 speed auto tranny, 3.42 gears in the rear end and there ain't no "Grampa foot" on the end of my leg. I average around 19 MPG with the truck at 75 to 80 MPH on 265/50/20" tires. I have a K&N FIPK along with a set of KOOKS long tube headers, and a EFI Live tune on the engine and tranny. The tune on the tranny closed up the shift points and made the transmission more useable for my driving. The engine as plenty of low end torque and the capability to push the speedo to well over 100+ MPH, since the fuel cutoff is now gone.

Re: My 2012 GMC Sierra
 

How is the Z71 package killing the gas millage?

Re: My 2012 GMC Sierra
 

Z71= 4 wheel drive= lower MPG. The average gas mileage on the new 4 Wheel Drive trucks appears to be around 15 to 17 MPG. Where the mileage for the 2WD trucks averages around 19-21. Unless you are going to the mountains, working in the country, or really driving in deep snow, the 4 wheel drive provides more pain than success. I have been driving 2 Wheel drive trucks for many years, now and I am very comfortable with my mileage and the fact that I get around as well as most 4WD trucks on the icey highways of Kansas. I am by no way knocking a 4WD, but in the long run, the mileage and wear on the extra drive components is costing the owner much more, unless he really has a need for the extra driveline.

Re: My 2012 GMC Sierra
 

Not all Z71's are 4x4's

Re: My 2012 GMC Sierra
 

I stand corrected, I was under the understanding that they were. I will say that the increased goodies and the heavy duty suspension and without a doubt, the gearing is an impact on the fuel.



General Motors released a slew of new images yesterday that show us what the Z71 off-road package looks like on two of the three GMT900 model SUVs. The Avalanche, Tahoe and Suburban are available with a Z71 package that adds, of course, the Z71 off-road suspension, new 18-inch aluminum wheels mounted on combination on-/off-road tires, an automatic locking rear diff, and high-pressure shocks. That's it for the hardcore mechanicals, though buyers who opt for the Z71 package are as much interested in the image these vehicles project as they are their capability. To that end, Chevy adds the Skid Plate Package, oversized wheel arch flares, tubular assist steps, extra bits of chrome trim, and rectangular fog lamps, along with the requisite Z71 badging so everyone knows you could go off road if you wanted to. The interiors benefit from a Z71-specific gauge cluster and brushed metal look for the dash. The Z71 package certainly adds some cajones to these GMT900 SUVs that will spend most of their lives on smooth pavement, and they also add some serious attitude, especially when ordered in all black.

Re: My 2012 GMC Sierra
 

The Z71 package consists of skid plates, high capacity air cleaner and a decal. I would say that the on-off road tires that came on my truck contribute to the MPG. I plan on putting less aggressive tires on when I need to replace the original tires.

Re: My 2012 GMC Sierra
 

Now why people buy 4wd and don't really utilize it to its full capabilities? As far as for myself, did I need 4wd? No, not really. Did I want 4wd? Yes :metal:

I drove a 1979 Nova 4 door for 5 years in the snow. I did get stuck a few times but managed always to make it home. It's all about how you drive for the most part.

I have a Honda Recon 250 quad that's 2wd. If I ride smart I can always keep up with the bigger 4wd quad's. But I will say that my next ATV will be 4wd :smoke:

Re: My 2012 GMC Sierra
 

The only thing a Z71 package has that the other trucks can't be optioned out for is Rancho shocks. The Z71 package comes with skid plates and a high capacity air cleaner, but you can get those options on any GM full-size truck. It's only the shocks that cannot be optioned out on there own.

The biggest difference now, is that when you order a Z71 you need to get an LT truck with a 5.3 or 6.2, which makes the package a $6-8k (cdn) upgrade. You use to be able to get the Z71 package on base model trucks, with a 4.8 and floor shift 4x4.

Re: My 2012 GMC Sierra
 

Actually you can option a 5.3 Z71 with 3.08's, so in some cases they should be better on fuel.

Re: My 2012 GMC Sierra
 

I added a LEER cap last November but I never got a chance to change out the door handles to the painted white ones I have.

Re: My 2012 GMC Sierra
 

so what is the advantage to having a 2wd Z71? I found 1 at a near by dealership. a 2011LT package. 2wd Z71 extended cab short bed 5.3 with 61k on it. I don't remember if it is a 6 speed or 4 speed automatic. they are asking $21,900 for it. I had a 2008 rcsb 4.8 4wd work truck and loved it for the three weeks that I had it. before I hit some ice on my way in to work one night and totaled it.

Re: My 2012 GMC Sierra
 

If it's a 2011 it's a 6 speed… If you run in an area with ice I'd look for a 4x4 and get some Winter tires… Personally I don't think the Z71 package is even an Offroad package, shocks and stickers don't make it better off road… It's more of a different convenience package offered by GM… I think it can tow a little more then a base truck can, but that's about it…