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TDiFonzo

Chevy Silverado Z71 MPG

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Guys

 

I own a 2004 Silverado with the Z71 package.Its got the 5.3 litre V8. Just gave it a fresh tune up (plugs,wires,air filter) and an oil and filter change. Tires are filled to 35 PSI.

On the last tankfull of regular gas,I averaged a little over 12 MPG city and hwy combined. Does this seem a little low? headscratch.gif

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I own a 2004 Silverado with the Z71 package.Its got the 5.3 litre V8. Just gave it a fresh tune up (plugs,wires,air filter) and an oil and filter change. Tires are filled to 35 PSI.

On the last tankfull of regular gas,I averaged a little over 12 MPG city and hwy combined. Does this seem a little low? headscratch.gif

 

 

 

Yup, very low. I get 19 mpg average with a Duramax 3/4 ton. Run the tank as low as you dare, fill it up, keep track of the mileage to make sure your computer isn't on the fritz. I had an '02 with the 5.3 that averaged right around 20. I would think an '04 would be better. headscratch.gif

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The drive gear ratio largely influences MPG. My 2002 GMC had a 3.72. My 2005 (5.3) has 3.42 and I get 21 mpg on highway in warm weather.....cold weather a little less. My 2002 3.72 got 19 mpg at best.

 

What's your drive gear ratio?

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I own a 2004 Silverado with the Z71 package.Its got the 5.3 litre V8. Just gave it a fresh tune up (plugs,wires,air filter) and an oil and filter change. Tires are filled to 35 PSI.

 

On the last tankfull of regular gas,I averaged a little over 12 MPG city and hwy combined. Does this seem a little low? headscratch.gif

 

change your fuel filter.... you will be surprise!!!!!!

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If the fuel pump (in the tank) is starved for fuel, it will burn the bearings.

 

Then the pump will make noise and could fail.

 

There is a high cost of running the tank very low on fuel, be careful.

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I own a 2004 Silverado with the Z71 package.Its got the 5.3 litre V8. Just gave it a fresh tune up (plugs,wires,air filter) and an oil and filter change. Tires are filled to 35 PSI.

On the last tankfull of regular gas,I averaged a little over 12 MPG city and hwy combined. Does this seem a little low? headscratch.gif

 

 

I have the same truck with the same engine. I average 17 city and 21 1/2 highway with a combined average of 18.1 on regular gas. Are you running the a/c? My milage drops a few mpg if I am blasting the air.

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Not sure what my drive ratio is. I'm guessing it's a 3.42 as well. I'm definately running the a/c. It's been in the mid 90's here in Florida pretty much every day for a few weeks now. I'll definatly check the fuel filter oout.

Even with the a/c running I thought I should be getting more than 12 MPG's.

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View Postchange your fuel filter.... you will be surprise!!!!!!

 

No fuel filter on the 2004. I believe they did away with them in 2002.

 

View PostNot sure what my drive ratio is. I'm guessing it's a 3.42 as well. I'm definately running the a/c. It's been in the mid 90's here in Florida pretty much every day for a few weeks now. I'll definatly check the fuel filter oout.

Even with the a/c running I thought I should be getting more than 12 MPG's.

 

If you have the towing package you most likely have 3.73 gears (same as in my sierra). What you can do is pick up chevron techron fuel injector cleaner. Its the same as what GM sells under their label. Clogged fuel injectors will certainly have an impact on fuel milage. Try that first. You will be amazed at the restored performance in the engine. I run a bottle after every oil change. I believe 1 bottle treats 20 gallons. You can thank me after you empty that first tank of treated fuelcwm27.gif

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View PostGuys

 

I own a 2004 Silverado with the Z71 package.Its got the 5.3 litre V8. Just gave it a fresh tune up (plugs,wires,air filter) and an oil and filter change. Tires are filled to 35 PSI.

On the last tankfull of regular gas,I averaged a little over 12 MPG city and hwy combined. Does this seem a little low? headscratch.gif

 

 

I have the same truck except mine is a 2003 - I get about the same as you, combined mileage 12.5-13, it really went down when the ethanol blends came to be. Just put in some injector cleaner, will see if it make a difference. I have two friends and a father in law with basically the same truck, they are all in the same ballpark as you and me.

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Ihave an 03 z71.5.3 and the 3.73 ratio,I always got @ 18-19 mpg.I added a fresh air intake,gibson single pipe exh.And a throttle body spacer.And now I am getting just over 20 on the highway..I would try changing the fuel filter.and running a good quality fuel injection cleaner through it.also,running the a/c and even using the cruise control will lower mileage like said above.good luck

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i have an 05 sierra Z71. Mine has a 5.3 aluminum block v8 which makes 310hp. I drive pretty easy most of the time. My city+hwy is like 14 mpg...On the hwy I do pretty well. Did a trip from upstate ny back down to the island a few weeks ago, I got 22mpg with a 17' canoe, camping gear, coolers, and fishing gear.

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I own a 2004 Silverado with the Z71 package.Its got the 5.3 litre V8. Just gave it a fresh tune up (plugs,wires,air filter) and an oil and filter change. Tires are filled to 35 PSI.

On the last tankfull of regular gas,I averaged a little over 12 MPG city and hwy combined. Does this seem a little low? headscratch.gif

 

 

 

Yes, this definately seems low. What did you get before the tune-up?

 

I also have a 2004 with the 5.3 litre and get pretty much what the EPA estimate is 15 city /18 hwy. Maybe a little better in the summer and a little worse in the cold weather.

 

PS. If you have the standard package you probably have the 3.73 axle ratio. If you look in your glove compartment there will be a sticker with all the codes for your truck's options. GT4 is the 3.73 ratio, and GT5 is the 4.10 ratio. Those were the only axle options you had available in 2004 on the K1500 4X4

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