Fuel Mileage

I currently am getting around 15 mpg. I have a 2002 1500 5.3 z71 ext cab short bed truck. Is this good? I put a new exhaust on it and noticed a small increase in the neighborhood of 1 mpg. I plan on putting a k&n on it within a few weeks and then getting a tune to try to move it up a little higher. With gas creeping towards 4.00 a gallon I would like to know some more tips for increasing my mileage. I run my tires at 55psi also. I had them at 65(max) but I am noticing some uneven tread wear and decided to pay a little more for gas than new tires. Thanks!

If you could find a way to safely disable knock sensors that might get you better mileage. JK! My SES light came on with bad knock sensors and during the week ive been driving it with the bad knock sensors ive been getting better gas mileage, not sure how much better but i can tell it is better. But im just joking, i dont think you would want to disable them, but i am getting better mileage, geting them fixed to day though.

i have the same truck and im getting 13 miles to the gallon. that is doing 120KM/h on the highway although my truck has 213000 KM on it. i also have a AirRaid cold air intake. personally i think this is crappy gas milage when i know of other similar trucks getting low to mid 20's. my reason is that my cat is probably plugged so im going to get some dual exhaust to help the old girl exhail a little better maybe it will help

I've got a 99 silverado 5.3L and I get about 15-18 with a light foot and mostly highway driving.

If you could find a way to safely disable knock sensors that might get you better mileage. JK! My SES light came on with bad knock sensors and during the week ive been driving it with the bad knock sensors ive been getting better gas mileage, not sure how much better but i can tell it is better. But im just joking, i dont think you would want to disable them, but i am getting better mileage, geting them fixed to day though.


if it were possible to disable the knock sensors this would cause the engine to run with the incorrect timing and this would cause engine damage.... this is a computer learned sensor output , and over a period of time adjusts to the voltage generated ....this is designed to give the maximum timing that is safe...

I currently am getting around 15 mpg. I have a 2002 1500 5.3 z71 ext cab short bed truck. Is this good? I put a new exhaust on it and noticed a small increase in the neighborhood of 1 mpg. I plan on putting a k&n on it within a few weeks and then getting a tune to try to move it up a little higher. With gas creeping towards 4.00 a gallon I would like to know some more tips for increasing my mileage. I run my tires at 55psi also. I had them at 65(max) but I am noticing some uneven tread wear and decided to pay a little more for gas than new tires. Thanks!

i changed the transmission and engine oil/fluids to synthetics... I gained 1.5 mpg , and the transmission shifting is faster esp. at below zero temps...also engine starts faster...........I get 18mpg max. hwy. on 2000 5.3L LT ext cab 4X4........this was done at 20,000mi. I now have 110,000mi.....

I have never got better than about 16.7 with mine. If it is mostly city driving it is anywhere from 13.5-14.5 It has 3.73 gears. Always use mobil 1. I also have a tonneau cover and cat back exhaust. There is just no way to get good mileage out of these things.

I have never got better than about 16.7 with mine. If it is mostly city driving it is anywhere from 13.5-14.5 It has 3.73 gears. Always use mobil 1. I also have a tonneau cover and cat back exhaust. There is just no way to get good mileage out of these things.

try synthetic in the trannsmission i bet you will pick up 1mpg.. that will be what i am getting...about 18mpg... i also have a bed cover it does reduce drag...i found putting the spare in bed also helps..as well as 65-70mph on hwy...over 70mph mpg falls off

you think thats bad? im getting 11 - 12 mpg city, on my 01' 4x4 silverado ext cab. dont ask me why. i have no clue and im not auto savy either.. its making me quite mad tho..

Ya'll are lucky I get 9mpg max around town on my 2002 2500 HD 4x4 gas.

maybe i will quit complaining.... i dont think i could afford that bad of mileage...

Me neither. I am getting around 16mpg with my 99 4.8L. That's why I only drive it on weekends around town. As far as I know it's 100% stock with 156k miles. My other car is a VW Diesel and I cant begin to tell you how happy I am to own that car(read: 45mpg).maybe i will quit complaining.... i dont think i could afford that bad of mileage...

I was going to start a thread on this same topic, but I found this one. I have a 00' silverado 2wd 5.3 xcab SB, I'm currently getting 13.5 on the highway, granted It has a Fabtech 7 inch lift with 305/70/16 Mickey Thompson MTZ's. But I feel it should get better mileage than that considering that the truck only has 115,000 miles.

2003 Silverado 1500 4X4, all stock, 69K miles. I get 15-16 driving around town/short trips (I live 2 miles from work, post office, grocery store, etc.). On the highway, I get 17-18 mpg, usually driving 75 mph. Best I've ever done is 19.9 driving across the state of Washington (I think I had a tail wind...). If I drove a constant 60 mph, I'd get over 20 mpg! Worst I've ever had is around 14 - in the winter with snow tires and all very short trips.

Art

MINE IS A '01 2500 HD 6.0L, MOSTLY STOCK. I GET 12 mpg/CITY, 15 mpg/HIGHWAY. ALL I ADDED WAS K&N AND A DUAL EXHAUST. I DO CLEAN THE AIR FILTER AT LEAST ONCE A MONTH, CLIMATE IS AWFULLY DUSTY HERE...

maybe i will quit complaining.... i dont think i could afford that bad of mileage...

I normally don't drive much in the winter months so the weather was finally warm and went for a ride 260mi.....hywy 70-75 mph and to my surprise the vehicle got 19.7mpg..... this is the most i ever got....the only thing i did since last fall when i last checked mpg was clean the MAF.....

I have an 01 5.3 ECSB with a Jason Camper Shell on it. I averaged my last tank to 16.9 mpg. I am in NH where there is still 4 feet of snow on the ground in some places.

The camper shell really helps although not right now because of cold weather etc.

I think my next oil change I am going to use that new Mobil1 0W-30 "Fuel Economy" synthetic oil. It says it does not void warranties etc.

I keep my engine clean and tuned etc. I have B&G fuel service every 20,000 miles, have all fluids changed to synthetic (diff, trans, etc).

I can get in the 20's with warm weather and cruise control.

I keep my engine clean and tuned etc. I have B&G fuel service every 20,000 miles, Excuse me for my ignorance but what is B& G fuel service and what do you mean by keeping the engine clean ??

They have by far the best intake and fuel cleanign system.

go to http://www.bgfindashop.com/locator/index.php

check it out. Find a shop nearby that does it. It requires special tools to do this. one part goes in the gas tank, one part through the fuel rail, one part through the intake manifold, and one part through the TB.

Some people also do the seafoam too. That works only to a certain point though. What I mean by keeping the engine clean is regular oil changes, fuel filters, pc valve, air filters, 2 cans B12 in every other gas tank, etc. I also keep the engine bay detailed most of the year :)

They have by far the best intake and fuel cleanign system.

go to http://www.bgfindashop.com/locator/index.php

check it out. Find a shop nearby that does it. It requires special tools to do this. one part goes in the gas tank, one part through the fuel rail, one part through the intake manifold, and one part through the TB.

Some people also do the seafoam too. That works only to a certain point though. What I mean by keeping the engine clean is regular oil changes, fuel filters, pc valve, air filters, 2 cans B12 in every other gas tank, etc. I also keep the engine bay detailed most of the year :)Thank You!

I have an 01 5.3 ECSB with a Jason Camper Shell on it. I averaged my last tank to 16.9 mpg. I am in NH where there is still 4 feet of snow on the ground in some places.
how the heck can you get 17 mpg. we have the same truck i think 2001 silverado ext 5.3L,LS. and im getting 11. i mean jesus.. why does the world hate me? when i bought the truck last spring i was getting around 15mpg. but this year i dont get it. i haven't done any improvements to it. regular maintenance.i drive gas consciously too.

I know how you feel trust me. There are some things you can do to a stock truck and get good gas mileage. You need to start with a good upper intake cleaning (B&G) or do the seafoam treatment through your brake vacuum line.

1.change rear diff. fluid to synthetic 75/90. Its quicker to warm up and causes less drag on driveline.

2. Use mobil1 oil and mobil1filter. (Yes the filter makes a difference up to 3/4mpg)

3.You could even try the newer 0w/20 mobil1. But most importantly use their mopbil1 high efficiency oil filter its a less restrictive filter than most on the market (They are $10 a piece).

4. make sure your tires are aired up real good. this makes a huge difference. I usually keep mine at 35-37 psi.

5. next fillup (DO NOT USE SUper, just low or mid grade gas) put 2 cans B12 (The metal cans, not platic bottles). If a fuel cleaner comes in a plastic bottle it aint good. REAL fuel system cleaner would melt a plastic bottle :) These cans are at walmart for $3 a can, I always keep a 6 pack on hand. use every other tank after three consecutive tanks of 2 cans. Make sure previous tank is almost gone before putting more in.

6. Check your plugs. You may not have noticed but GM changed their spec on spark plug gap. Your engine may have the stock 0.60 gap, but now they call for 0.40 gap. USE ONLY AC/DELCO!!! No fancy quad-firing neon ultra gold mega spark plugs, ok? These are the real deal Iridiums. This gap change makes a difference.

7. Change the usual suspects: PC valve, air filter (just use Fram, no oil based ones), fuel filter, etc.

After these few things, your PCM will "Lean-back" and you will noticed improved mileage. I drove 3000 miles this summer from S. Texas to New Hampshire and I promise you these things work. You do not have to "mod" the engine out to get some really good mileage.

If you can afford a tonneau cover or camper shell you will gain an additional 1mpg. I have reached 22mpg unloaded on the highway at 70mph with the above mentioned things and a camper shell. I also keep my truck clean and waxed, I do not know if this actually makes a difference but my truck looks good!

Good luck man, gas is only going up from here!!!!

Hanibal, good tips, thanks.

Keep the tips coming guys. I'm sick of spending all this money filling up my Sily tank.

What's the deal about the MAF sensor? That needs to be cleaned?

Also, how long does a cat converter last? I've got 130,000 miles on my 5.7 gas '98 K1500. It runs good, but I just feel I should be getting better mileage.

It truly sucks that here we are driving these EFI vehicles and still getting crappy mileage. :banghead:

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Hanibal, good tips, thanks.

Keep the tips coming guys. I'm sick of spending all this money filling up my Sily tank.

What's the deal about the MAF sensor? That needs to be cleaned?

Also, how long does a cat converter last? I've got 130,000 miles on my 5.7 gas '98 K1500. It runs good, but I just feel I should be getting better mileage.

It truly sucks that here we are driving these EFI vehicles and still getting crappy mileage. :banghead:

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if o2 sensors are 130,000mi replace them 30,000mi over due...clean maf with crc maf cleaner follow directions do not touch the small sensing wires..

if your mileage still sucks check for restricted exhaust or knock sensors that are going bad....

My 1997 Z71 ext cab 4x4 gets around 20 mpg highway, maybe 22. Here's what I do:
1. Check the inside driver door label and upsize your tires to the larger size IF you drive mostly highway, as I do. The smaller tire gives better city mileage. Larger tire requires more energy to get rolling. But once you are cruisine, each turn of the tire covers more distance on the groung. About two mpg gain.
2. I run slick 50 in my engine oil. Flush your block with a quart of flush from autozone. Old timers used to use tranny fluid to do this. Not as good as what we have now. With outside temps at 105 degrees and running the A/C at max, I noticed at least a 10 degree drop on my temp gauge. It definately reduces friction. About 1mpg gain.
3. I use platinum plugs. Platinum acts as a catalyst in combustion. In other words, it accelerates the combustion, more power. That's why it's used in catalytic converters, to help complete the combustion of exhaust gases. I recommend a 3 prong bosh platinum plug. 1-2 MPG
4. I put a soft top cover on my truck. People argue over whether or not it helps counter the effect of "tailgate drag". It did on my ext cab. About 2 mpg. It also keeps my stuff dry.
5. Get rid of the "junk in your trunk". Hauling a bunch of tools, gravel etc is going to consume more fuel. Keep only what you need in your truck.
6. Air flow. Keep your air filter clean. You don't have to replace it, just take it out and blow air thru it in the reverse direction of the normal flow. Or upgrade to a better system, like K&N.
7. Not sure about the tranny fluid, but I agree synthetic is probably better. My tranny is currently having issues....
Hope this helps!
JMR

I am sitting at 19.5 miles to the gallon with mildly aggressive mixed city and highway driving. I still havent got the tune that I wanted to get. I do have the KN coldAir and Flowmaster Exhaust. I would guess it is your 4X4 killing it. My truck is an 06 2wd and my buddies is an 05 4X4 and he gets the same mph as you.

My mpg went from 16.5 to 20 after I aired up my tires from 35 psi to 45 psi (265/75/16 BFG AT's) which is almost where it was before I changed replaced my old 255/70/16 Generals.

My 05 Z71 usually gets between 14.5 and 16 around town, depending on how I drive and where I get the gas. On the highway its usually around 17, but have gotten 19 before. Mostly stock, but has a retuned computer, cold air intake, and custom exhaust. I also always have a tool box in the back with all kinds of crap in it. So I could probably get better if I got rid of some of that stuff, and got a lighter foot.

I've got a 2002 4.3L, mostly hiway miles just put on an intake to see what it will do. I was averaging 18mpg before.

I have a 2000 GMC with a 4.8L and I get 15 in town and between 19-21 on the highway if I keep it under 75mph. Two ways to increat mileage almost instantly is;

1) Remove any excess weight in the truck (tools, crap in the bed, spare tire.
2) Sell it and by a smaller car.

No way around mileage on a 6,000 pound truck.

I have a 2000 5.3L with AEM cold air intake and cat back system and I'm getting 16mpg around town. Not sure about highway though because I don't do much of that.

Oh yeah, I've also got a 6" suspension lift and 35" tires so I guess I'm lucky getting the mileage I get.

:banghead:
I am having the same issues with my 05, 5.3L CrewCab (40,000 miles). Up until about 3 weeks ago I was getting 19+ mpg hwy and about 17 city. Then my wife (her truck) noticed the city mileage was tanking. Now it's about 14mpg. We took a trip into Fort Worth this weekend and my hwy mileage was a measley 15mpg. I ran 2 cans of seafoam into the fuel and changed out the AC Delco Iridiums for a new set. She had cleaned the K&N filter a week prior to the trip. On the return trip the mileage improved but only to about 16.5 mpg. I don't have a check engine light so I am thinking that the only thing that would interfere with the engine performance without giving me a CEL would be the MAF. I assume the way to clean it is to remove it from the air tube and spray it down with CRC MAF approved cleaner, is this right? About the knock sensor; doesn't that produce an error code when it goes bad?

:banghead:
I am having the same issues with my 05, 5.3L CrewCab (40,000 miles). Up until about 3 weeks ago I was getting 19+ mpg hwy and about 17 city. Then my wife (her truck) noticed the city mileage was tanking. Now it's about 14mpg. We took a trip into Fort Worth this weekend and my hwy mileage was a measley 15mpg. I ran 2 cans of seafoam into the fuel and changed out the AC Delco Iridiums for a new set. She had cleaned the K&N filter a week prior to the trip. On the return trip the mileage improved but only to about 16.5 mpg. I don't have a check engine light so I am thinking that the only thing that would interfere with the engine performance without giving me a CEL would be the MAF. I assume the way to clean it is to remove it from the air tube and spray it down with CRC MAF approved cleaner, is this right? About the knock sensor; doesn't that produce an error code when it goes bad?

On both my vehicles i have k&n air filters....this winter after reading some comments about cleaning the maf and also internet searches on k&n air filter issues with the maf, it appears that proper drying of the filter before running the engine is necessary, or the maf will get coated with oil.....



after cleaning my maf i took a 250mi ride and as i got to the 100mi point i new it made a difference in mpg.

upon filing up tank after the trip i got 20+mpg....but also the throttle response was better....it's been 6mo. and the engine is still much better mpg and smooth power response..CRC cleaner.....it works and its safe..

I Recently Replaced Transfer Case Fluid And Both Frt. And Rr. Axle fluids As Well. I Will Let You Know On Mileage Variation Once I Filled Up 2 Or 3 Times...

OK. Our engines all have an ECU (engine control unit). This control unit does what is called closed-loop control. That is, it uses feedback from the O2 sensors to make sure that the air/fuel ratio is where it is supposed to be.

So, how can oil from the K&N filter mess up fuel mileage. If the MAF reading is wrong, the engine will burn rich or lean, and the O2 sensors will see it. This should cause adjustments to be made to make the air/fuel correct again.