For reference - 2007 Chevy Suburban 1500 4x4 5.3L gas/flexfuel mileage - hard numbers

[Z-Michigan]

For anyone curious, here is my gas mileage for the first 5400 miles of driving a 2007 Suburban 1500 4x4 with the standard 5.3L gas engine (with AFM and E85 capability). This driving is about 70% commuting (mix of highway and city) and 30% pure highway/freeway travel. I have not done any towing or heavy hauling. There are no mods, but I did switch to synthetic engine oil (Pennzoil Platinum) at 1600 miles. These are all hard numbers from the odometer and gas receipts, no trip computer iffy numbers or optimism. % ethanol in the fuel is a guess except when I've bought E85 or when indicated on the pump. The overall average so far is 16.94, compared to EPA numbers of 15/20 (old system) or 14/19 (new system).

The AFM feature (v4 mode) comes on all the time on the freeway when on the slightest downhill or sometimes even on pure flat ground, even at over 70mph, and fairly often in highway cruising. I doubt a non-AFM motor would get nearly as good mileage in this driving.

I am running 34-35psi cold pressure in the tires, which is above the minimum of 30psi but well below the tire ratings for max pressure and leaves me with a good ride and no apparent tire wear issues.

The tank of 19.9mpg was a mix of highway and freeway driving in Indiana in fairly mild weather, but at normal speeds and including some hills (Brown County). I think 60-65mph is a sweet spot for getting best mpg in this vehicle. I have noticed that mileage is terrible when cold, and being able to drive 200+ miles at a stretch without the engine cooling off probably helped the mpg.

The last four tanks were on 89 octane midgrade, which I'm experimenting with to see if it improves mpg - it would seem to, but all four tanks were mostly freeway driving so I don't yet have a large enough sample to be sure (though most of those four tanks also saw a lot of 4wd use in snowstorms, which just muddies things further).

Odometer Reading Gallons Purchased Date Trip Mileage Trip MPG Fuel % Ethanol This Fill % Ethanol in Tank 3-Tank Average
282 0 10/11/07 n/a n/a gasoline 5 5.0%
475 10.934 10/15/07 193 17.7 gasoline 5 5.0%
858 22.542 10/19/07 383 17.0 gasoline 5 5.0%
1232 22.226 10/25/07 374 16.8 gasoline 5 5.0% 17.06
1396 9.962 10/30/07 164 16.5 E85 85 30.7% 16.83
1812 25.469 11/04/07 416 16.3 gasoline 5 9.6% 16.55
2189 21.2 11/07/07 377 17.8 gasoline 10 9.9% 16.90
2480 14.627 11/08/07 291 19.9 gasoline 10 9.9% 17.68
2819 20.256 11/16/07 339 16.7 gasoline 5 6.7% 17.96
3015 12.27 11/21/07 196 16.0 gasoline 10 8.0% 17.52
3272 15.164 11/24/07 257 16.9 gasoline 5 6.5% 16.61
3487 13.136 12/05/07 215 16.4 E70 70 33.4% 16.47
3791 19.097 12/11/07 304 15.9 gasoline 5 15.9% 16.37
4029 14.552 12/16/07 238 16.4 gasoline 5 10.8% 16.18
4379 21.943 12/23/07 350 16.0 gasoline 10 10.2% 16.05
4569 10.759 12/24/07 190 17.7 gasoline 10 10.2% 16.46
4819 13.71 12/27/07 250 18.2 gasoline 5 7.9% 17.02
5183 20.764 12/30/07 364 17.5 gasoline 5 5.9% 17.77
5457 15.821 01/02/08 274 17.3 gasoline 5 5.5% 17.66

 

[hudr]

Re: For reference - 2007 Chevy Suburban 1500 4x4 5.3L gas/flexfuel mileage - hard numbers

Those look pretty close to what I get from my parents' '99 2WD 'burb w/ a 350. Low of around 13mpg on straight city/short trip and a high of 19.6 on a long open road trip from E TX to Denver, CO.
Straight gasoline, though.
Looks like it may be worth fixing the A/C and driving it another 125k miles.

 

[john_bud]

Re: For reference - 2007 Chevy Suburban 1500 4x4 5.3L gas/flexfuel mileage - hard numbers

Interesting.

I used to have a 5.3l in a 2000 Z71 ext cab short bed 4x4. It towed 10k about 40% of the time. Lifetime average from odo and fuel bought was 16.076 mpg. Low of 8.6 towing a 10k load with a large wind sail area during the winter and a high of 20.6 all freeway for 250 miles at 65 mph in the summer.

Typical was 14 to 18. All towing 10k load was about 10 to 11 mpg at 65 mph. Typical mix with no towing was 17-19 mpg. Truck lifetime mph from the odo and hour meter was 39.4 mph.

I'd have to say that it appears the improvement in technology has not yielded a substantial gain in fuel economy.

Thanks for sharing. Post again when you have a chance to tow some weight and then again after it's broken in.

jb

 

[ToadHill]

Re: For reference - 2007 Chevy Suburban 1500 4x4 5.3L gas/flexfuel mileage - hard numbers

I have a 97 Ford F150 with the 4.2 V6. Most all my driving is a mix of city and highway at almost a 50/50 rate. Summer mileage is 16 to 17 and winter is 15 to16. It has been the same since I got the truck.

 

[Z-Michigan]

Re: For reference - 2007 Chevy Suburban 1500 4x4 5.3L gas/flexfuel mileage - hard numbers

John-

Given that we also have a diesel 3/4 ton, I don't see I'll be towing more than 2k with the Suburban. No real point even getting a brake controller installed in it. As for break-in, I would think (???) it would be broken in at 5400 miles. Supposedly there isn't that much break-in any more, but who knows.

I agree it doesn't seem like much if any mpg increase vs. your 2000 model. Two comments though. First, an extended cab pickup from the MY2000 probably is 600-800lbs lighter than a Suburban, which makes a big difference. Second, I am assuming all my gasoline is 5 to 10% ethanol, while something you bought in 2000 and already sold or traded probably spent most of its time with you on truly 100% petroleum gasoline, which could add a couple % to your gas mileage. (I realize Wisconsin is also a corn state, but the ethanol boom really only started around 2005 as far as I can tell, at least anywhere but Iowa and Nebraska.)

Anyway, since I record all these numbers and have been following the other debates about whether people "really" get the mileage they claim, I figured posting hard data on this and our diesel would be useful.

 

[john_bud]

Re: For reference - 2007 Chevy Suburban 1500 4x4 5.3L gas/flexfuel mileage - hard numbers

Z,

Yeah a Dodge diesel is a very good tow machine.

I assume that your 'burb is 2WD? The truck was 4x4. So, it's probably a real close weight between the two. It scaled at just over 5k. Wisconsin has been adding 5-10% ethanol for years and years. I don't know that there were many tanks that were not at least 5%. I make a thoughtful effort to buy gas with ethanol, higher cetane rating and all.

I am pretty sure that we could buy E85 here in 2000 - it's good to be in a corn state. I just wish they would get some bioD stations around here. 2% is supposed to be good for the pump and injectors.

jb

 

[Z-Michigan]

Re: For reference - 2007 Chevy Suburban 1500 4x4 5.3L gas/flexfuel mileage - hard numbers

My Suburban is a 4wd with Autotrac. Empty weight is around 5800lbs. (GM says 5743 lbs estimated for the 1500 4x4, but since I have a couple options and since manufacturers notoriously understate the weight, I think 5800lbs is safe if not low.) So it sounds like I was right on with the weight difference.

Specifications: Suburban: SUVs: Chevrolet

Here in Michigan we grow a lot of soybeans and so biodiesel is relatively easy to find, especially outside of town. I have run B20 fairly often in both Dodge and the former Liberty CRD and it works great in each one. Noise and smoke are noticeably lower, mpg was unchanged, and there was no downside I could see. Where we live now it's not as convenient to get as it used to be, but we still put it in the Dodge when convenient. It's another fuel that may or may not make sense from both economic and environmental perspectives, though.

 

[Kahuna]

Re: For reference - 2007 Chevy Suburban 1500 4x4 5.3L gas/flexfuel mileage - hard numbers

For comparison sake here are the stats on my last three trucks:

1999 F150 4.2 V6 5 speed manual 14 mpg (on a good day)
2004 F250 5.4 4 speed auto 12-13
2007 Tundra 5.7 6 speed auto 15.5-16.5

This is with a 10% ethanol blend.

 

[Kahuna]

Re: For reference - 2007 Chevy Suburban 1500 4x4 5.3L gas/flexfuel mileage - hard numbers

I just posted the previous message about the mileage of my last three trucks I owned. I forgot to mention all were 4x4 which will decrease the mileage somewhat.

 

[john_bud]

Re: For reference - 2007 Chevy Suburban 1500 4x4 5.3L gas/flexfuel mileage - hard numbers

Z-,

Yeah, I thought the 'burban was lighter than that! The Z71 was autotrac also. That was a seamless system. Just press the button and when you wanted more traction there it was. Too bad the 2500 HD can't get one.

I used to have a '78 burban C25 with 454 4v. 2WD. It was 14.0 to 14.4 on the freeway and 7-8 towing. But, I had to keep right on top of the tune. Diddle with the carb jets and idle screws, fuss and bother with the distributor, air cleaner, clean the plugs and everything. It would migrate down to 12 pretty quick if you didn't. It did tow like a banshee.

Sold it to a buddy with horses. He pulls a 4 horse aluminum trailer with it. When his car wouldn't start at -20F, the burban that had sat for 3 months outside untouched fired right up. He still tows with it. Good truck.

jb