2015 Chevy Silverado

[firefly1957]

.In September i replaced my 2003 Impala with a 4 wheel drive Chevy 2015 Silverado standard cab with a 6 1/2 foot box, 6 speed automatic, and 5.3 L engine that switches to run on 4 cylinders on light loads. The sticker boasts 23 hwy MPG how ever i have never gotten that i am wondering if any of you have similar trucks and what your mileage is?

. I talked to the dealer a month ago and an engineer both said there is a software update for my truck i took it to the dealer Friday and they said no updates and the truck has no codes showing they drove it and it showed 20 mpg at 60 mph on level road. I told them it often shows that but the average both on the computer dash display) and with fuel use /mileage calculation is much lower. On the way home i reset everything and at a 60 MPH speed i averaged 15.7 MPG for 15 miles , at 70 MPG it averaged 15.8 MPG for 15 miles , Bumping the cruise control to 78 for 15 miles made an average of 15.4 MPG. The computer was reset for each speed, roads are fairly level here honestly i had a 1978 Dodge Ramcharger with 440 cid engine that dis almost as well on mileage. This truck does get better mileage at 30-40 MPH the instant mileage reading differs very little whether it is running on 4 or 8 cylinders for instance it may say 20 MPG at 60 MPH on 4 cylinders then 18 at 60 MPG with all 8 cylinders running . The information displays can be distracting there is so much information available and then add the sound system and it is worse yet!

[DCP]

I have the same truck

21mpg was the best it ever done

over the road I get 18-19
Now when I let it warm up for 10min and drive 2 miles to work I get 11-12

If you have a heavy foot you can sure see the difference
If you want to talk send me a pm with your phone # and I will give a call

[C. Latch]

I have a 2001 with the 5.3 (extended cab, z71, etc, etc) and mine always runs on all 8 cylinders and gets 16-18 on the highway.

I don't think the fuel management technology is worth the cost. Also, I'm not sure the extra electronics will survive as long as mine's been running. I passed 400,000 miles back in December.

[MarkP]

I rented to 2015 Chevy 1/2t crew cab with a 5.3 L and drove it from Omaha NE to Garden City KS (near Colo & Ok border) just under 1,000 miles in one day. The computer matched the calculated mileage very well.

Overall average was right at 21.0 mpg and one leg was 23.6 mpg. On the way home I was driving around 82 mph and the last leg was mid 19's. I do not recall the wind diractions or conditions but it is usually windy were I was driving. Also rented a 2014 with a 4.8 L and drove it to Denver with a pretty good head wind and it got 11.0 mpg. My older heavier 6.0 L would have done better.

The computer mileage on my 2003 3/4T with 6.0L is always very close to the calculated mileage. My running average for this truck is 12.75 can get up 14.5 at times and will get near single digits in stop and go traffic.

[Ehaver]

I have an 07 Tahoe 4x4 with the 5.3 The best highway I have ever gotten was 20 mpg on 93 octane. Avg. is 16 with city/highway on regular gas. I was hoping for better but I does not look like that will happen. My wife's car gets wayyyy better mileage with premium gas, but not this beast.

It also does the 4cyl 8cyl dance.

[Powder Burn]

I have a 2009 Avalanche with 5.3 and gets 21 on highway. Pulling an aluminum boat it drops to 15.5. I've had 3 Avalanches over the years with the 5.3 doing about the same thing. Can't remember the rear end ratio but it is a 4x4. Your mileage seems low to me, but if it is new I'm sure it will do better after a few more miles. I always get better mileage on a new truck after 10,000 miles or so.

[firefly1957]

Thanks for all the answers i have ordered a cap for it took it to the dealer just to see if they could find anything when i get the survey back i will give them negative remarks . I know some vehicles will do better then others the truck does go like crazy and has good traction i did not have to use 4 wheel drive until the snow was a hardened foot deep . I tow a 5500 pound boat/trailer towing it i get 9 MPG my 1990 Chevy Van got 12 MPG and MY Motor home gets 8.5 towing the same boat . Like powder burn mentions i only have 4200 miles on it it may loosen up a bit
C. Latch i think you are correct they would be better off adding a two speed rear end for when in 2WD rather then reduce running cylinders, the truck has of torque and turns 1500 rpm @ 60 mph it could be 1100 rpm i bet. I also worry about all the information inputs not just for the engine but suspension as well i can see going though half a dozen dismiss issues* each time the truck is started over 100,000 miles.

* acknowledging the problem to see the dash displays

[funnyjim014]

Its mostly due to the colder weather. The longer the engine takes to get up to temp the longer the ECM will run in open loop ( ie preset data to get it up to temp faster, does not use the O2 sensors as they dont start reading untill there hot). Alot of people complain about the milage on all cars. The sticker on thewindow of all new cars is what the car scored on a closed driveing course someplace in CALIFORNIA under the best driving conditions. Expect aprox 20-22mpg in the summer with fuel that contains zero ethanol. O fyi if you decide to go green and run E85 ( if it is a flex-fuel vehicle with the yellow fuel cap) expect 10mpgMAX.

[osteodoc08]

I had a 2010 with the 5.3 and cylinder deactivation. I could get 21-22 on a flat road, cruise 60mph. Otherwise I averaged 18 in real world driving.

I have a 6.2L in my Yukon that went toe up at 6x,xxx miles. It was replaced and now have issues with the brake assist wanting to lock the brakes down that they cant track down since it was replaced.

My neighbor has a 5.3L with 150K miles. Runs and drives well, but burns 1qt oil every 3k miles or so, which seems to be common with these motors with the cylinder deactivation and higher mileage.

[30Carbine]

You want to talk fuel millage 2003 chevy 2500 hd. 3 miles to a gallon all day loaded or not. oh yea I almost forgot I did put a chipped up 502bbc in it after the *** dirtymax blew it's lid.632hp and 721ftlbs of stump pulling torque.

[Lloyd Smale]

I have a 2015 short box 4x4 club cab 5.3. If I just let the gas mileage reading go for about a month (my wifes truck and she drives it) it will show about 19 mpg. that is a 5 mile one way trip to work and a 5 mile return everyday and driving through town and an occasional 60 mile trip to the bigger town around here. My 06 gets about 16 doing the same. Best mileage I ever got on a trip was 19 with the old truck and last summer we went to green bay and I checked it (Highway only) and driving for the most part about 65 and not trying to save gas and got 24.2 on the way down and 23.9 on the way back. Keep in mind that I put a borla cat back on it new (don't know if it helps but I seriously doubt it) So for the most part it consistently beats out my 06 by 3 to 4 mpg. All that said I still worry about the cylinder cut out. I know the 2011-2012s had a lot of major motor problems blamed on the cutout and lots of them used excessive oil. They claim to have fixed in in 2014 and I will say that mine has about 2ok on it now and hasn't needed a drop of oil. Keep in mind too that the difference you quote between 20 and 18 mpg is a big increase on a full sized truck. Very few if any modifications will net you that 10 percent increase in gas mileage. I mostly drive my 06 and to be honest still am impressed all the time by even it. If I really baby it it will do 20mpg and I can remember very few years ago that if you could do that with your family car you were bragging to the world about it and the old chev 1/2 tons I drove were a challenge to get over 12 mpg out of.

[bullet maker 57]

I have a 2000 2wd Silverado with 165,00 miles. It has the 5.3 and a 3 speed tranny with OD. I get 17 to 18 mpg no matter what. Empty or towing a trailer. Does not use any oil between changes. Mobil one at 7500 miles.

[bayjoe]

I've got a 2011 that gets 21 to 23 mpg and have 166,000 miles on it and it is still going strong. Doesn't use oil nor leak any either.

[Minerat]

I have a 2000 3/4 ton 6.0 liter 4x4 with 215,000 mi on it, getting 12.3 every day in town and if you set the cruse it gets 15-16 on the highway at 75. It has been this way since day 1. Put a 7000# atv trailer on it with tow/haul pressed and haul it over the straight creek tunnel and Vail pass it gets 12 mpg at 65 mph. Still does not use oil or leak either. Using Mobile 0ne. I really don't care what the mileage is, it's a truck first with a big engine that does what I need. If I want a gas saver I'd buy a VW diesel, sell my boat, atv's quit hunting elk and take up knitting.:kidding: I have grown immune to low gas mileage as I sold my 4x4 van that got 4-8 mpg for this 2000 pickup so 12 looks good to me.

[firefly1957]

My truck CAN NOT USE E-85 all the gas here has 10% ethanol i forgot about the GM systems dropping mileage in cold weather Ford does not do that it seems . Warmer weather coming and putting a top on it hopefully fuel mileage bumps up a bit. By the way none of the mileages i gave above was from cold start system was reset while at speed on the highway except for total trip which has never read over 17MPG.

[runfiverun]

the tires can make a big difference too.
i swapped out my summer all-terrain tires for the winter ones [off road type] and dropped mileage.
from 22 regularly to 19 mostly.
they are the same diameter around it's the rolling resistance that makes the difference.
i could tell right off when i took the cruise off to roll off the freeway and had to feather the gas pedal to make it to where i normally roll to a stop at.

[Handloader109]

It isn't just gov motors trucks:-)
My 2005 F150extended cab gets 20mpg at about 65mph with temp at 75 or above. Will drop to 15mpg if it is close to freezing.. Hates cold weather.

[leeggen]

Your going to drop about 2 mile to the gallon with a topper that is even/close with the cab at a minimum. Yeah that stinks but if you want a topper that is what it is. My toyo tacoma got 24 on highway til I added the topper then it went to 21. I had a cold air intake installed and increase it back to 24 highway and 20 in city. I have the 6cyl. and it is a 2011. Breakin on the truck probably won't increase the milage most of them don't anymore. There has been times I got 26 but that was just after towing the 16 ft. flatbed trailer, got 19 towing it. Hey you just pay the gas price and go on, the dealer won't do anything to help. Once the warrenty is out have a good mechanic reset the fuel/air ratio, then the milage will go up.
CD

[firefly1957]

Handloader109 we have a 2009 Mercury Grand Marquis and a Motor home on a E-350 chassis neither lose mileage in cold weather.
Leeggen I was considering the Tacoma .

[leeggen]

Firefly1957 we considered the 4 wheel drive in the 2011 but it would loose another 5 mile to the gallon. We were going from a 1996 pontiac Boniville getting 32 mile to the gallon and milage was important. Have not had any complaints with the taco. I don't runhard nor hotrod anymore, finally out grew that. No hugh payloads to pull now so that fit the. We checked each brand and then plugged in what we required and drove and tested the ones that were selected. Hard choices out there as most were basicly the same. Just happen the toyo won out. Like I mentioned after warrenty find a good mechanic and have him tune the computer up so you get a better fuel/air ratio. You have to watch the chips, some your onboard computer will readjust back to factory settings.
CD

[Lloyd Smale]

I have a nephew with a full sized Toyota v8 pickup that weights less then my sliverado and gets 18mpg at best. That's at least 5mpg less. My take on the new Toyotas is there good reliable trucks but probably 5 years behind in real technology. I think they feel they have the American customers so blinded to thinking there better that they don't have to keep up with technology. I know they were a full 5 years behind gm and ford in switching from throttle body to multi port injection and I don't think they still have caught up to direct injection. they ran 5 speed manuals and 4 speed autos well after the competition put manuals to the history books and run 6 and 7 speed autos. figure out some day how much 5mpg difference cost you over 200k and factor in your probably going to pay more for the Toyota to begin with and you might finally have your eyes open
Firefly1957 we considered the 4 wheel drive in the 2011 but it would loose another 5 mile to the gallon. We were going from a 1996 pontiac Boniville getting 32 mile to the gallon and milage was important. Have not had any complaints with the taco. I don't runhard nor hotrod anymore, finally out grew that. No hugh payloads to pull now so that fit the. We checked each brand and then plugged in what we required and drove and tested the ones that were selected. Hard choices out there as most were basicly the same. Just happen the toyo won out. Like I mentioned after warrenty find a good mechanic and have him tune the computer up so you get a better fuel/air ratio. You have to watch the chips, some your onboard computer will readjust back to factory settings.
CD

[firefly1957]

Llyod Smale I never looked at the full size Toyota just the 6 cylinder Tacoma my Chevy is getting 15-16 MPG that is worse then the big Toyota . I had a 1978 Dodge Ramcharger with 440 cid engine 3 speed automatic that did as well.

Leggen thanks i will look into it I am mostly running empty except when i tow 5500 pound boat /trailer then mileage is 9 MPG lower than it should be .

[Lloyd Smale]

pretty amazing gas milage for a 440. I know my gtx 44o 323 gears and an auto tranny didn't get 12 and it was much lighter then a ram charger. Heck my v6 stick mag Dakota would only do 16 and my dads newer Dakota with a 318 mag and an auto doesn't get better then 16-17 either. From what ive been told by the owners even the little 4 cyl stick 4x4 Toyotas don't do much better then 22 and I can do that in luxury in my full sized chev. Now to be fair compare your Tacoma not to my full sized truck that gets 23 mpg(better then any tocoma) but to the midsized colorados that do 25 that are the same size as your Toyota and youll really see how far behind in technology Toyotas are.. Absolutely only thing I regret with my 05 is I didn't wait another year. The new z71 chevs are hands down the best looking truck anyones made in years.
Llyod Smale I never looked at the full size Toyota just the 6 cylinder Tacoma my Chevy is getting 15-16 MPG that is worse then the big Toyota . I had a 1978 Dodge Ramcharger with 440 cid engine 3 speed automatic that did as well.

Leggen thanks i will look into it I am mostly running empty except when i tow 5500 pound boat /trailer then mileage is 9 MPG lower than it should be .

[Fishman]

I have a 4wd 2000 model z71 with the 5.3. I get 15 in mixed driving, 16.5 on the interstate, and 13.5 towing my small boat. It has 280,000 miles on it and still uses no oil. After seeing CLatch's post, maybe mine is just getting broken in.

[Fishman]

I remember our 96 dodge neon. It was rated at 29/38, and we broke 30 mpg on the interstate one time. I know the fuel economy figures are calculated a little differently now, but it wouldn't surprise me if they were a little optimistic. I see the same pattern with our '08 Honda Accord although not as big a difference.

[firefly1957]

Lloyd in the trucks the 440 got the best fuel economy at that time a friend had a Van got 18 MPG . My second 73 charger had a 69 440 engine in it i got 18 mpg back and fourth to work a girlfriend had a 68 Chrysler 300 that when fed the required premium fuel got 25 mpg on the hwy.
Fishman i am glad to hear how long this trucks last this should not be a high mileage truck no long trips unless it is fishing to the U.P. I knew a few people had Neons and hated them none of them got great mileage my 03 Impala did better giving me 29 back and forth to work and 32+ on trips when i put pure gas in it i got 33.5 mpg on a trip to Nashville .

[historicfirearms]

My Honda gets 25 in the winter and 28 in the summer, so temp does matter, or at least maybe tire pressure or snow friction. Best car I ever had for mileage was a 1995 V8 camaro. I could get 32 mpg with it on the highway. The wife's Malibu was supposed to do mid 30s but best we've ever done is 26. Our work truck f250 gets 8 mpg and it's a 2015.

[AnthonyB]

I have a 2008 F250 Turbo Diesel and have logged every gallon of fuel that went into the tank. I am averaging just about 16 MPG over close to 60K miles and consider that amazing given the 8000 lb. weight of the truck. I feel perfectly safe against anything up to a bus or semi while driving it.
Tony

[Mk42gunner]

You know if we would suddenly take the ethanol out of gasoline, everybody would get an immediate 3-4 mpg boost. I know the F150 I was driving when the ethanol mandate came down went from 17 mpg to 14 mpg with no other changes.

Robert

[Freightman]

You know if we would suddenly take the ethanol out of gasoline, everybody would get an immediate 3-4 mpg boost. I know the F150 I was driving when the ethanol mandate came down went from 17 mpg to 14 mpg with no other changes.

Robert True but the stations that sell straight gasoline charge an extra $0.20 a gal canceling the savings.

[Sweetpea]

True but the stations that sell straight gasoline charge an extra $0.20 a gal canceling the savings.

20 cents a gallon is easily worth it.

Around here, there is ONE pump with regular gasoline, and it is a dollar more per gallon!

[Lloyd Smale]

around here ethanol free 91 octane sells for the same price as 93 octane with ethanol. I think the price difference most here are seeing is the difference in regular and premium gas.

[firefly1957]

Everywhere i see gas without ethanol it is at least 70 cents more a gallon except in Wisconsin. I may try it in the truck some time to see the change.

[firefly1957]

Update at 5500 miles my fuel economy went up the down adding a bottle of octane booster bought mileage to 19.5 highway @ 60 - 78 mph truck also spends more time in V-4 mode then running all 8 cylinders. Yesterday i got my cap for it drive down (100 miles) i got 19.5 mpg drive home i got 20.5 mpg . Next tank full i will add octane booster then try a couple tanks without to see how mileage goes.

[DLCTEX]

True but the stations that sell straight gasoline charge an extra $0.20 a gal canceling the savings.
I my info is right, there is only one station in Amarillo that sell non-alcohol gas and it is trucked from Oklahoma City.

[firefly1957]

Fuel economy dropped again :sad: