SUPERCHARGE

Hi, peeps, don't know if you remember my post 2 weeks ago about me freaking out about taking my truck on a 1600 mile (round trip) road trip to see my sick grandfather. My problem was that I had recently installed LPP headers and haven't had the time to tune the truck. This worried me greatly as I only had limited funds available and was worried about the gas mileage a de-tuned truck would give me. Well, did I ever have a pleasant surprise when I topped the fuel up after traveling the first 247km and only spent 27.32$.

I calculated everthing in deatail. I filled the truck up before leaving, kept the prices I paid when gassing and fueled up at destination to get the exact amount I spent on fuel. Here are the facts:

According to my GPS and odometer, the trip was 1281km (one way) = 800.12 miles. (1600.24 round trip)

fuel prices were 95.9cents/liter.

I spent 147.89$ going up and 143.72$ coming back.
with prices at 95.9cents/liter, that indicates I spent 154.2 LITERS (40.74 GALLONS) going up and 149.86 LITERS (39.56 GALLONS) coming back.

So all in all, I did 19.64 miles/gallon on the way up and 20.23 miles/gallon on the way back. NICE!

Here's the thing too. 2 thirds of the trip was highway (i'd travel at 62-67 mph) under 2000rpm. The last third was very mountainous and curvy backroads of the north where I'd have to accelerate and brake quite a bit.

Strange parts is that the way back was very very busy with lots of construction, took me an additional 2.5 hours to travel, yet i managed to do better gas mileage than on the way there (which i had traveled at night). I'm assuming this may be because I replaced the air filter while at my granfather's house.

So doing an Average of 20 MPG on a 2002 4x4 Sierra with a detuned 5.3liter engine (over 130 000miles) is definitely not bad.

Any idea why I would of gotten such good fuel mileage when the highway mileage on a NEW truck is supposed to be 17? Could the header replacement with the low speed I was traveling make such a difference?

andrew383

iTrader: (14)

going about 60-65 i get 20-21mpg and i have 3.73's.What gears do you have?

SUPERCHARGE

Really? Nice, so it's not impossible to get a very decent gas mileage. I'm not sure what my gear ratio is. I'm guessing it's also 3.73 as it's what most factory 5.3's came with.

garcia

that is some good mileage.I am getting less than what you are getting but I have 3:42 gears

nonnieselman

iTrader: (10)

Thats not too bad..
I got a Blackbear Tune for a friend of mines truck and he gained about 1mpg. he decided to use 93 octane and he went from 18 to 19 on 87oct and 19 to 21 on 93 octane.

Truck was bone stock.



I went on a 1400 mile road this past weekend.. first 150miles i got 9.5mpg
I havent had time to really sit down and tune since the cam install. Just added some fuel and hopped for the best.
After the first 150 miles and correcting my tune and adding timing i went from 9.5 to almost 16mpg towin a trailer

AFRs were low 11s when they should have been mid 13s and timing was really low in those areas. Corrected the fuel table and added some timing, Vola!!

01HO

Maybe you can give me some help? We just bought a loaded 04 Z71 burban with a 5.3, it is getting around 12 on the hwy. I plan on sevicing ALL fluids, change plugs/wires and maybe cold air kit/exhuast to help this gas hog. We picked it up fairly cheap (9500.00) but it does have high miles 143k. I would be very happy with 19 or 20hwy. Any help would be VERY appreciated!!

Thanks,
Jeremy Homeyer
White, 2004, Z71, Burban,143k, stock for the moment

00ChevyScott

iTrader: (10)

From what I've seen most 2wd trucks came with 3.42s and the 4wds had 4.10s

gtosilverado

iTrader: (3)

i drove from houston to mcallen, roughly 350 miles. goin pretty much 65mph all the way, and crossed several small towns, so had to slow down, and some traffic lights... i used up about 16gallons, gas gauge was just a bit under 1/2 a tank. thats about 22mpg. my truck has 3.73s

050n20s

I am seeing great gas mileage right now with LPP headers installed also. around 65-70 mph I can see 21 - 22.8 mpg on highway. City is 17 -19 if I cruise.

tank454

From what I have seen, most 5.3 4x4's have 3.73's, but I have seen a few that were ordered wit 4.10's