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Poor Fuel Mileage 2007 Silverado 5.3l New Body Style


spartus

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Posted

I'd like to know why so many of us with the new body style 2007 trucks are seeing such poor fuel mileage out of these? Is there some type of service bulletin out by GM covering this? Such as a newer PCM flash, or parking brake known to drag? I'm lucky to get 12 mpg around town, and 14-16 on the highway driving like Miss Daisy in my 4x4 Crew cab with 5.3 and 3.73's... That is well over a 25% discrepancy. Sounds like False advertising to me. BTW, I towed a 3000 lb trailer and got 8 mpg on a 140 mile trip. What's going to happen if I try to tow a 7,500 lb trailer? Stop at every gas station?

 

The advertisements from GM just don't add up. They were advertising 20 mpg up until several weeks ago, now I see the TV adds saying 22 mpg. I have YET to talk to anyone with one of these new trucks that has seen close to that. GM must have done something on the 08 trucks to scew the #'s even more in order to figure 22 mpg.

 

If any of you techs have any ideas, please let me know.. Thanks.

 

As of this writing the truck has 4,400 miles on it.

Posted

2200 miles on my 2007 Silverado 1500 5.3 2WD and the sticker said 22mpg. I work out of town each week and average around 140 miles on the commute each way and the best I can get going 70 miles an hour is 17.46 miles per gallon. Going with the wind and against it. I think I'm going to call BS on those gas claims.

Posted
It's a truck not a honda. :)

 

I'm sorry, but I'm talking to the GM techs. Please keep your idiotic comments to yourself.

 

 

 

Ganudorm: If you can find that memo it would be appreciated. I know at times it can be something simple such as a known caliper or parking brake to hang. Usually this can happen in batches, and you have a certain group of vehicles with a certain issue. I work for an OEM so have experienced things like that before.

 

 

 

Thanks.

Posted

Holy cow. My '06 5.3 4.10 gets 15 around town, 17 highway, and 12.4 towing 8500 lbs on the interstate between OH and WV. I got better than 8 mpg last time I towed 5000 lbs with almost a ton of hay on the back of the truck on backroads. Now I'm really proud of my truck hearing this :-)

 

Matt

Posted

the mpg that is on the sticker is ideal mpg. every truck/car will differ from one anouther. with only 4400 mi on it, 4x4 and 5000+ lb and all, i would not expect better then what your getting now. put some more miles on it. my 03 SS didn't start getting good milage until about 15-17000 mi. i now have 35,000 and can get 17.5 mpg @75mph and 22+ @ 55. also E85 is killing ALL of us when it comes to MPG. :)

 

good luck

 

:chevy:

Posted

Why do you say E85 is killing all of us when it comes to mileage? If you don't use E85 it shouldn't affect your mileage. It is worth it around here to burn E85 when you find it, is is about $1 less a gallon.

Posted

Whoa! Gotta agree with you on this! My 99 Z71 w/ 5.3 and 3.73 did about 18.2/17 highway/overall. My 02 Z71 w/ 5.3 and 3.73 does 17.5/16.5 highway/overall. Both of these trucks would average overall less than 1 mpg under the EPA highway mileage, and would beat the EPA highway rating out on the road. My wifes 99 Gran Prix GTP would also beat the highway EPA rating. Something seems wrong.

 

If you are dragging a brake, you'll notice it if you feel your wheels after running a few miles. They should not be too hot to touch. If they are...bingo, but I doubt that this is it.

 

Keep us updated with what you find. I'm interested in getting a new truck, but not if it won't beat my current ride in mpg.

Posted
I'm sorry, but I'm talking to the GM techs. Please keep your idiotic comments to yourself.

 

Hey, c'mon, man.....have some respect....the guy was just making a joke....chill out. Maybe you NEED to get a Honda....it might teach you some manners!

 

Back to topic....you can never go by what the dealers post for gas mileage on the sticker sheets....it doesn't really reflect real life. If you can accept 10% below the posted numbers, then you're doing ok.

Posted
I'm sorry, but I'm talking to the GM techs. Please keep your idiotic comments to yourself.

 

Hey, c'mon, man.....have some respect....the guy was just making a joke....chill out. Maybe you NEED to get a Honda....it might teach you some manners!

 

Back to topic....you can never go by what the dealers post for gas mileage on the sticker sheets....it doesn't really reflect real life. If you can accept 10% below the posted numbers, then you're doing ok.

 

 

If we were to keep the KIDS off of here, everything would stay on topic. Maybe you can go buy a Honda.

 

I'm 25% off of what the sticker says.... Quite often I only get 15mpg highway... And I drive a lot of highway. 300+ miles per week at times.

Posted
I'm sorry, but I'm talking to the GM techs. Please keep your idiotic comments to yourself.

 

Hey, c'mon, man.....have some respect....the guy was just making a joke....chill out. Maybe you NEED to get a Honda....it might teach you some manners!

 

Back to topic....you can never go by what the dealers post for gas mileage on the sticker sheets....it doesn't really reflect real life. If you can accept 10% below the posted numbers, then you're doing ok.

 

 

If we were to keep the KIDS off of here, everything would stay on topic. Maybe you can go buy a Honda.

 

I'm 25% off of what the sticker says.... Quite often I only get 15mpg highway... And I drive a lot of highway. 300+ miles per week at times.

 

For your info I'm not a kid...and I DO own a honda along with my truck. Get a sense of humor and drink a beer.

Posted
Holy cow. My '06 5.3 4.10 gets 15 around town, 17 highway, and 12.4 towing 8500 lbs on the interstate between OH and WV. I got better than 8 mpg last time I towed 5000 lbs with almost a ton of hay on the back of the truck on backroads. Now I'm really proud of my truck hearing this :-)

 

Matt

 

I have a 2004 5.3 with 3.73 and I was averaging 16.3 with mixed city & highway driving before I got my wait4me PCM. Now I am getting 17.1 and it seems to be improving after only 1.5 of driving it. Looking at my average speed of around 30 mph, I do pretty good and I can only hope that on the interstate, I would do good as well. I will be going to Myrtle Beach the last week of July and will see what I get then.

 

It is good to see someone else on here from not very far away too.

Posted

Maybe I should also point out that my 2003 OLD TECHNOLOGY 1500 with 5.3L would get 18-21 on the highway, and 16 around town. That is why I'm so irritated.

 

Also, I don't buy it that a vehicle has to break in, in order to get better milieage. I've never had a truck get better gas mileage as it wore in. None of my cars either. Our 1998 Buick with 3.8L got 26 mpg new, and to this day still gets 26 mpg with 129,000 miles on it. The wife is now driving 700 miles per week, compared to my 300+, so she gets to drive the car.

 

 

 

For all I know, the dealership washed down the cylinders in the engine before I purchased it. It had 60 miles on the odometer, along with 7 hours of run time. That is a lot of idle time.

Posted
Why do you say E85 is killing all of us when it comes to mileage? If you don't use E85 it shouldn't affect your mileage. It is worth it around here to burn E85 when you find it, is is about $1 less a gallon.

since they have been using the E85 mix here in CA ( winter gas ) i have dropped 1.5+ in mpg. we have no choice but to run the mix :) 100% E85 is rated at about 102-103 octane, and yes it is cheaper this week, but it will not give you the same mpg as gas.

don't get me wrong, the E85 is a coming thing for fuel and i do want clean air for my grand kids, but when your paying almost $4.00 per gal for 91 here every little bit helps...and what really sucks is that all the products that deal with corn products, like milk, beef here is going through the roof. :chevy::bs:

$5.00 a gal for milk is :bs:

 

sorry I'll get off my soap box

 

:seeya:

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