MPG Numbers

MrQuadrasteer · December 6, 2003

Took a trip to Corpus for Thanksgiving, the truck's first trip. After 550 miles and 'cipherin', I'm pretty happy .

Cruise @ 83mph, occasional a/c = 13.1mpg !!! Not so good.....

Cruise @ 74, little more a/c = 14.2mpg ... much nicer.

Cruise @ 65.... 16.7mpg ?!!!? Whoo-hoo.... not bad at all .

Too bad I can't drive 65 !!!

Also found the DIC to be pretty spot-on, <.5 mpg difference.

And very nice ride .

Anyway, thought someone might be intrested !!!

OUMike · December 6, 2003

thats really pretty good for that 6.0L. I'll have to do that to the ol' 4.3..

CapnDean · December 6, 2003

4.8 18-19 mpg 70% hwy 30% city per tank.

Hwy is 75-85 range (75 to work 85 on the way home gee I guess you know my priority)

99silveradoz71 · December 6, 2003

I've got a 22mi trip each way to work now instead of the 8.5 I used to have. I'll have to check the last few tanks to see what I've done since the move. Only problem is the road driving after getting off the freeway- stop signs, lights, etc.

MrQuadrasteer · December 6, 2003

Well, I didn't mention.... those were strictly highway-miles. Around town- which is 97% of the time or better- it gives 10.2~10.8mpg.

gould10 · December 8, 2003

2003 z71 suburban 3,000 miles only getting 14mpg

durado · December 9, 2003

I have a 2003 Suburban LT 5.3. Recent trip, 3200 miles with 2600 being highway 70 to 85 mph, I got 17.8 mpg for the entire trip. The best leg I got 19.8 mpg.

The burb was loaded, wife, 3 kids (smallest was 6 foot, 13 year old) luggage and 4 dogs.

MrQuadrasteer · December 9, 2003

I have a 2003 Suburban LT 5.3. Recent trip, 3200 miles with 2600 being highway 70 to 85 mph, I got 17.8 mpg for the entire trip. The best leg I got 19.8 mpg.
The burb was loaded, wife, 3 kids (smallest was 6 foot, 13 year old) luggage and 4 dogs.

Dang.... 'em some big kids !!!!!!

I'm heavy-footed and I know it. Like I said, you buy something like this and then complain about mpg ???? Not to me, please !!!!

TedHam · December 10, 2003

I get close to 20mpg on the highway using my cruise control religiously and avoiding heavy acceleration with my miserly 4.8L, Auto. And with 3.73's.

gould10 · December 10, 2003

Durado, have you always gotten 17mpg with your suburban? I thought I would get closer to 16mpg, guess not. maybe it will do better when it gets more miles. It gets it's first oil change friday. I love the suburban really nice. I knew the mileage wouldn't be great just hopen for a little more is all.

AZ-Z71 · December 10, 2003

I get way better gas mileage out of the 5.3 (3.73 rear) when I keep the speed between 75 and 85 on the highway somewhere around 17.5 to 18 mpg. In town probably more like 15 mpg.

Got to drive my dads Dodge Ram this weekend and the past two days, I swear it only got 10 to 12 mpg and that was with most of the driving on the highway. All I know is that I put about $40 in and probably only did like 250 miles. (98, 5.4??)

durado · December 10, 2003

I have about 11000 miles on my Sub. I run 42 psi in the stock Firestone tires, K&N replacement filter, Tornado, TB coolant by pass and the air chambers in the stock air intake tube closed off. Did these things when I first took delivery of the truck. First oil change, relied on the oil life indicator about 7400 miles went to Mobile 1 5-30.

JayMan · December 10, 2003

In summer, 100% highway miles on a trip, cruise at 70-75 MPH, 18-20 MPG. Depends on wind conditions too.

In summer, 100% city stop-n-go, 12 MPG. That's with the A/C on too.

In summer, split of 60% highway, 40% city, average 15.5 MPG.

In winter, 17 MPG on the highway, average about 12 MPG depending on city driving and idle time.

Michelin LTX M/S tires, thinking of Michelin Cross Terrain SUV.

FWIW: I consistently picked up 1.5 MPG city and 3 MPG highway after switching everything to synthetic oils.

Lance Link · December 10, 2003

I get close to 20 mpg on the highway with the Z-71 and generally average 16-17 overall (I check my mileage each time I fill the tank).

The Yukon has averaged 16.4 mpg since new, according to the trip computer.

J-rod · December 10, 2003

Hmmm, while I don't check my mileage for daily driving (I have a ~10 mile commute to and from work each day ... 90% highway), I have checked it on a few trips so I know what I get on the highway at least. For me, I've consistently gotten ~17.5 mpg. I'm guessing I could've gotten a little better if I'd have watched my speed more, but instead I was somewhere betwee 75 and the limiter (98 on mine ... and no, that wasn't often, mostly up 85 but I got bored a few times and had nice, long, open stretches to play ).

Mods:

K&N (drop-in replacement)

Flowmaster 40 series (single 3" in / dual 2.5" out)

So pretty much stock. Oh, and I always run regular (87 octane) gas. I've seen several ppl here mention running 89 in their stock trucks ... can you tell a difference? Obviously I don't have any ping (I'd better not since 87 is what GM recommends), but theoretically it *should* improve mileage. Does it help enough to notice though? And the bigger question, does it help enough to make up for the difference in price?