Poor Gas mileage 2003 Jimmy with 4.3 liter Vortec

Is it normal for a 2003 Jimmy with 5000 miles on it to burn 22 liters of gas to go 120 kms on the highway? I believe this works out to about 15 miles per Us gallon.

I questioned GM Canada and was told that I had to wait until there was 5000 kms (3000 miles) before the dealer could do a fuel consumption test. I have had the vehicle back to the dealer twice and all I am told is that there are no stored computer codes, it passes diagnostics and the are no available software updates.

The sticker in the window when I bought the truck stated "25 miles per gallon highway" (in Canada I think the English gallon is used on the sticker, which is about 1.1/4 US gallons). The salesperson said that because I wasn't getting the 3.72 rear end and a two door was lighter than a four door I should expect better than this.

I got a different story a week after I bought the truck and questioned him on the gas mileage. I was then told not to expect more than 20 miles per gallon for our climate.

I was wondering if in fact this truck does have the 3.72 rear end. Is there anyway I can tell this , be it from the VIN or a sticker somewhere inside ?

Any help would be greatly appreciated.

Reply to
Bob Cook
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5000 | kms (3000 miles) before the dealer could do a fuel consumption test. I have | had the vehicle back to the dealer twice and all I am told is that there are | no stored computer codes, it passes diagnostics and the are no available | software updates. | | The sticker in the window when I bought the truck stated "25 miles per | gallon highway" (in Canada I think the English gallon is used on the | sticker, which is about 1.1/4 US gallons). The salesperson said that because | I wasn't getting the 3.72 rear end and a two door was lighter than a four | door I should expect better than this. | | I got a different story a week after I bought the truck and questioned him | on the gas mileage. I was then told not to expect more than 20 miles per | gallon for our climate. | | I was wondering if in fact this truck does have the 3.72 rear end. Is there | anyway I can tell this , be it from the VIN or a sticker somewhere inside ? | | Any help would be greatly appreciated. | |

Keep in mind that gas mileage can be ¼ to ½ less than "normal" during the

1st 3-4 miles of winter engine warm up. So, overall winter mileage can be adversely impacted just for that reason, especially if one makes most trips that are under 10 miles. But there is more that can impact mileage! The published mileage ratings for GM vehicles are done with the DRLs turned off...so running with the DRLs on can also account for a fraction of a mile per gallon (certanly less than 1MPG impact normally, but will multiply the loss during times when the engine is cold and running inefficiently to generate the power for the added lighting load...probably equating to over 1MPG). Winter driving also requires the use of other high power items, like the rear window defogger, the A/C compressor (for defrost cycles), headlamps/taillamps and the cabin fan running on high speed. All require heavy electrical power that uses horsepower from the engine to generate it, adversely impacting fuel consumption.

I had a 2003 Malibu that would only average 16-18MPG in the winter for my

4-mile commute into the office...about 22MPG in the summer....but I would get 31MPG+ (the most was 34MPG) on long road trips. Quite a difference! My guess is that 15MPG average for winter use is not unusual for a Jimmy with the 4.3 engine. But I would expect you to get 22MPG-24MPG for long road trips (once broken in).
Reply to
James C. Reeves

It should say on the window sticker what type of rear it has. I've never gotten anything over 22 mpg (US gallons) highway on my 4.3 s10. Look on the inside door of the glove box. There are codes on a sticker that will tell you what type of rear you have. It might take some research on your part to decipher them.

Reply to
Rob
15 sounds right, I know I can kill a tank a week with my Sonoma with the 4.3. Whenever somebody comments, I just say, "It's a good sized engine with the aerodynamics of a 4000 pound flying bathtub".
Reply to
Supernoma

IT PROBABLY IS MY 02 SUBURBAN 5.3 GETS 13 MPG/18MPG

Reply to
EPSYCHOBOB

Reply to
Stuuder

Bob,

It depends on how you are coming up with this number. I have a 1999 Jimmy with the 4.3L engine. I also have a trip computer aboard. My average highway/city driving is about 18.5mpg (60% of my commute to work is highway). If I set the reset trip computer before I leave for vacation, I get a number of about 21mpg/highway (This would be at a maximum of 65-70 mph.). I notice, that when I exceed 70 miles per hour, the fuel economy drops drastically.

I have also performed a city driving test. In that test, I found that fuel consumption was about, 16.5 miles to the gallon.

In short, never trust a salesperson. They will say what you want to hear.

You could also increase your highway mileage by using the cruise-control, if your truck has it. Most drivers can't maintain an even speed, on a long trip. I include myself in that statement. It's because driver's tend to pass vehicles to make time.

Do this for one week: 1.) Fuel your truck to the full mark. (record the odometer) 2.) Wake-up early, so you have no rush to get to work. 3.) When you drive the truck to work, use moderate acceleration from a stop, and don't exceed the speed limit. (Meaning, ..don't try to pass anyone). With any luck, you will have time to pick-up breakfast or a coffee, by the time you get to work. 4.) At the end of the week, fuel-up the truck, and record the miles/Km. 5.) You might find that this truck can come close to the E.P.A. posted consumption rates.

My Jimmy is a 4 door 4wd, and I can get close to the posted MPG, when I'm easy on the accelerator.

In the summer, with the a/c on, I get about 17 mpg total. The a/c will take away mpg, Big-time.

GMdude

Reply to
GMdude

Most Blazers get at best on sticker 16 to 20 in 4 door and the 2 doors get a bit better so that dosent sound to far off with the cold weather

Reply to
John

The EPA rating is 23 mpg on the highway for 2WD automatic, or 19 mpg for 4WD automatic. Your consumption works out to about 12.8 mpg (US).

First off, how did you measure the consumption? Best way is to fill tank until the pump shuts off, reset trip odometer, drive, and then refill tank and calculate from the mileage and the fuel added.

Cold temperatures will certainly reduce the gas mileage, and some engines tend to have worse fuel economy at low mileage. Your mileage still seems a bit low, but maybe not unreasonable..

Reply to
Robert Hancock

I'll agree with everyone here, the truck isn't a fuel miser by any means. I have a 94 4x4 4-door Jimmy, 4.3L automatic and a 3.42 rear axle. With the 20 gallon tank, with my normal driving, I'm starting to think about getting gas at 220 miles or so, and that runs the tank fairly empty. I've gotten over 15 MPG on my last 3 tanks, and it's been pretty cold here. I've gotten up to 23 MPG on the highway in the summer, on several occasions. My commute is 7 miles each way, with

2/3 of it at 45-60, depend>The EPA rating is 23 mpg on the highway for 2WD automatic, or 19 mpg for 4WD
Reply to
Mike Levy

Reply to
Stuuder

That is cool stuff. I like to see more of that truck. Are you display that truck anywhere?

Reply to
Paul

Reply to
Stuuder

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