What Fuel Mileage Do You Get With A 6.2l?

superjim · May 20, 2008

Just curious...

What kind of mileage do you guys get with the 6.2L ?

I may be in the market for a new truck soon, and I have always believed that there is no subsitute for CUBIC INCHES.

In reading some of the numbers from the 5.3L poll... I wasn't too impressed with them.

The bigger engine may get almost as good, because it don't have to work so hard pulling the heavy truck down the highway. Thats what I am trying to find out.

Thanks for any and all replies. Good or bad.

Bostonsfavson · May 20, 2008

I did some pretty controlled testing awhile ago after I got my tune. I did runs several times in both directions on a local highway and averaged the results. Keep in mind the truck has AWD and the 6L80E transmission. These are the numbers of the stock (untuned) PCM. The tuned PCM returned only very slightly improved numbers.

65 MPH: 19.67 MPG

80 MPH: 18.27 MPG

Around town I get about 14 in the summer, 12 in the winter. You won't be disappointed with the 6.2 Jim, especially once it's tuned and TM is removed

D&SYukonDenali · May 20, 2008

On AWD 07 YD, get 18 mpg (75% highway)

Bish · May 20, 2008

I average 15mph mix city and highway. I can get as high as 18 LOADED with family of 4 and lots of stuff but that's if I keep my foot out of the pedal which I find tough to do. Averaging 80-90 I get just below 15mpg.

I had an 01 Tahoe with 5.3 and with the exact same commuting route, I get 15mpg with the Denali and 13mpg with the Tahoe so I get 2 more mpg with 20% more cubes and 100HP more. Great deal IMO. I'm guessing the six-speed has more to do with better mileage than anything else.

superjim · May 21, 2008

Thanks for the answers guys.

I really appreciate it.

Seems like the 6.2L are not much worse then the 5.3's for mileage.

Keta · May 21, 2008

I think 21.2 was the highest I got on a long long trip averaging between 70-75 mph. This past weekend was in the lower 20's on the highway and 18's around town. I recently got a tune but I haven't noticed any mileage increase yet. I actually think the mileage comes from the 6.2's wonderful power, it effortlessly moves the truck down the road. Downside is the 6.2 likes 93 octane.

superjim · May 21, 2008

I think 21.2 was the highest I got on a long long trip averaging between 70-75 mph. This past weekend was in the lower 20's on the highway and 18's around town. I recently got a tune but I haven't noticed any mileage increase yet. I actually think the mileage comes from the 6.2's wonderful power, it effortlessly moves the truck down the road. Downside is the 6.2 likes 93 octane.

I have driven a couple of 6.2's. I also like the easy way they move down the road. Plenty of POWER.

I am used to the Premium fuel thing. I have a Cadillac Performance Sedan which also uses Premium.

music · May 21, 2008

The new EPA economy numbers are probably an accurate guage between the two for "typical" driving patterns. Sierra Denali AWD 6.2L @ 12/18 :: Sierra 1500 CrewCab 4wd 5.3L @ 14/19 city/hwy.

User polls get responses from:

a) the "driving on eggshells" folks that push the numbers way up just to prove that they can,

b) the "man-o-man that beast gots lots of power" types who get way low, and

c) the rest of us.

Add to that the inconistent terrain, driving conditions, etc. across the country and it gets worse. The EPA numbers are for nearly identical conditions. I know that everyone knows this... but I've already written a response now, so I might as well "post" it.

Bish · May 21, 2008

One other advantage of the 6.2L and 6-speed.....went to the track last night and ran a 14.7 second 1/4 mile completely stock except for a tune. Surprised many that didn't think a 6000lb brick could break 15. With 20" rims no less. Beat a Mustang GT but got SMOKED by a vette. Tune was worth approximately .4 second as I did some before and after runs.

jmac · May 21, 2008

I am averaging 15 city. If I really baby it I can manage 15.5. On the highway the best I can manage is 18. The numbers are much better than my Ford F150 4x4, which was 12 city and 15 highway.

Daubs · May 21, 2008

Wife's Yukon Denali is getting around 14 MPG city and ~18 highway. She kind of drive it like she stole it

I agree with the bigger engine works less to motivate truck. When looking for CC 4x4 back in 04 I talked to and read a lot of posts by 6.0 owners. They were getting 11-12 MPG from their 6.0's. I really liked power of the 8.1 and felt I could get around that from the Big Block. And I am. Consistently around 11 MPG city and 13-14 highway. Engine doesn't work very hard to motivate my big-assed 6,000+ plus truck!

Lincoln30 · May 21, 2008

My overall average (from DIC) from day 1 thru 10K miles is 12.2. It was 13 before winter, went as low as 11.9 and is now slowly climbing again. I have AWD, fairly large AT tires and a very heavy foot. It's the same mileage I get in my 99 5.3 w/ 4.10s when it's in stock tune...I get consistent 14.5mpg on the 99 with a Westers performance tune.

superjim · May 22, 2008

Mucho thinks to all of you for the information.

I don't see any advantage to going with the smaller engine.

In reading the 5.3 mileage poll....There are a LOT of 5.3 guys that are not getting any

better mileage than the 6.2.

Some of them, in fact, are getting quite a bit WORSE.

Looks like if I get a 2009, I will go with the 6.2, unless someone has a good reason NOT to.

Any and all comments are VERY welcome. This is a big purchase.

Bostonsfavson · May 22, 2008

Jim, I really can't think of a reason not to go with the 6.2 engine. It's just a great engine. I know a couple guys around here with the 5.3 and, as you said, they're really not getting any better mileage than me (plus I have AWD).