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Crappy Gas Mileage

Avalanche2002

Charter Member
Full Member
Joined
Jan 23, 2002
Messages
19
Just bought my Av 2500 and am quite disappointed with the gas mileage. I don't want to jump to conclusions as I only have about 700 miles and from the threads I've read on various websites, my mileage should increase. As of the first fill up, my around town mileage was 9.65 mpg. OUCH! :-X Most of the threads that I've read have said between 11-14 mpg. Maybe it's my lead foot, although I am actually trying to watch it. I've seen that people have added FIPK's and etc to enhance both performance and gas mileage. Any insite would be greatly appreciated. Nontheless, I am really jazzed about this rig; especially the ride, power, handling and braking.
As a side note, anyone else going to the rally in Seattle in June?
 
By you owning a 2500 I'm guessing you have the 8.1L.
Getting 9-10 mpg in that big sucka is pretty good to average. I've got the 5.3 in the 1500 and avg 13 in town. The only way to get better milage is to leave it parked and buy a hybrid car.
 
Av2002....I would definitely recommend getting one of the FIPK spoken about in this forum.....the most popular seems to be th K&N, but nonetheless consider it.

I've seen an improvement in my gas mileage with my 1500.....this is not with an aftermarket exhaust which is coming shortly...
 
When you buy the 2500 with the 8.1L you but it for the power, not the gas mileage. The 2500 is a power beast and just as hungry. My mileage for the first full tank fulls was about the same 9 MPG. I has since increased to about 10.23. I hope to new air filter from will increase it to about 12 MPG. I would bey happy with that. One more thing. When you use this beast to tow, the highway mileage is about 17 MPG. Will be leaving for FL from NY soon and will see how good this beast is on mileage when towing a long distance. Will let you all know.
 
Try adding some Marvel Mystery Oil to your next gas tank.

It helped several of my cars gain modest improvements. You might get an extra 25 miles per tank.

I'm trying it again now on my 1500 - will report later
 
First tank after adding Marvel Mystery Oil to the fuel:

375 miles on 25 gallons = 15.00 mpg, mixed highway and mostly city (phoenix) miles. ;D

Prior to this tank, I had gotten :

12.8 :mad:
13.5 :p
12.2 :cautious:
13.8 :cry:

I'm telling you guys, that stuff WORKS. :D

I'm converting to Amsoil Synthetic oil at 4500 miles, and that, combined with MMO, should allow us to get about 18 mpg on the freeway.

Will keep you posted mi amigos !!!
 
Anyone that buys the 2500 should not be concerned about gas mileage.. I have 2200 miles on mine now and the best ive seen is 15 mpg @ 70 mph. Around town 10 is probably the average.. :) :)
 
Hey, Thanks for all the input!

gandolphxx was right. After my first fill up at 9.65 mpg, my mileage did go up. My latest around town driving fillup was 13.9 mpg!!! :eek: I can't wait to see what I'll get on the freeway!

for a 3+ ton rig with an 8.1 L big block, I'm not complaining anymore. So I ate a little crow for talking too soon!

BTW, if anyone looks at www.edmunds.com and looks up the chevy AValanche, the editor rates the car a 7.5/10 and gives it an Editor's Most Wanted Rating. The consumer rating is a 9.2 which rates nearly as high as any of the Toyotas or any other new car for that matter. Chevy did a great job with the AV.
 
Marvel Mystery Oil update:

Latest tank = 14.80 mpg. That was ALL short trips, virtually zero highway miles.

Staying consistent...... ;D

Laterz............
 
???what does the marvel mystery oil do that gives you better mileage. I would think some kind of top engine lubrication. We used to do this to clean it out everyonce in awhile, but never did it on a new vehicle???????????
Does it smoke any?
zeeya
 
zeeya2000 said:
???what does the marvel mystery oil do that gives you better mileage. I would think some kind of top engine lubrication. We used to do this to clean it out everyonce in awhile, but never did it on a new vehicle???????????
Does it smoke any?
zeeya
I'm not sure HOW it works.....It's like when you turn on your computer - you know BASICALLY how it works, but as far as the DOWN TO THE GRITTY details, you're just not sure.

I have seen a LOT of posts about MMO on the web, and it seems to be a general agreement that the stuff DOES increase gas mileage. I guess that's the MYSTERY part of it, eh? ;D

The first time I tried it was on a trip to Austin back in 1992. I got about 60 more miles on that tank, so I was sold.

As far as smoking, no it does not.

I'm gonna stop using it after I go to Synth oil.....after all, using MMO does add a few cents to the cost of a tankfull, even with the benefit.

Laterz...........
 
I finally had a chance to do a quick road trip this weekend. Had to pick up my son from his friend's house up near my folks' cabin. About 100 miles round trip. Maintaing about 70 on the interstate and only having to tromp on it once or twice for left lane slow pokes, I was very impressed to get 19.12 (92.2 miles @ 4.82 gals). I filled the tank before I left and re-filled at the same station when I returned. I can assume some variance but even if I got 18 MPG, I'd be ecstatic! My 99 Expedition, which I turned in to Ford Friday night, never got above 17 MPG (was a lease). City driving always seems to keep mileage around 13.5 - 13.85.

Total mileage on the odo thus far: 1977.

Jamie
 
lars-ss said:
Marvel Mystery Oil update:
Latest tank = 14.80 mpg. ?That was ALL short trips, virtually zero highway miles.
Staying consistent...... ;D
Laterz............
Latest MMO update:

15.21 mpg (426.3 miles on 28.02 gallons)

Gas mileage has been increasing slowly, with no changes in driving habits. In fact, we have been in the 90s temperature-wise in Phoenix lately, so this last full tank was with A/C on most of the time, city driving.

3100 miles on the AV so far - inching toward the end of the break-in and itching to get that Synth oil put in !!! ;D
Laterz.......

 
lars-ss said:
Latest MMO update:
15.21 mpg ?(426.3 miles on 28.02 gallons)
Gas mileage has been increasing slowly, with no changes in driving habits. ?In fact, we have been in the 90s temperature-wise in Phoenix lately, so this last full tank was with A/C on most of the time, city driving.
3100 miles on the AV so far - inching toward the end of the break-in and itching to get that Synth oil put in !!! ;D
Laterz.......
Last tank, WITHOUT Marvel Mystery Oil added to fuel:

13.65 mpg (400.6 miles on 29.346 gallons)

So looks like to me that MMO really affects mileage in my AV. I'm going to use it this tank to check again. 3989 miles on the AV so far.....almost AMSOIL TIME !!!
Laterz........

 
lars-ss said:
Last tank, WITHOUT Marvel Mystery Oil added to fuel:
13.65 mpg ?(400.6 miles on 29.346 gallons)
So looks like to me that MMO really affects mileage in my AV. ?I'm going to use it this tank to check again. ?3989 miles on the AV so far.....almost AMSOIL TIME !!!
Laterz........
Latest results - next tank after that one quoted above, this time WITH MMO:
14.05 mpg (414.5 miles on 29.503 gallons)
I am concluding that Marvel Mystery Oil *DOES* have a positive impact on mileage for My Av.

This weekend I am converting to full synthetic Amsoil engine oil, so I expect even higher mileage next report. ( Less friction ya know matey. ;D)
Laterz........
 
half-breed said:
When you used 29 gallons what did your fuel gauge read? Mine will read empty and I only got 26 into it.

I believe we discovered in an earlier thread last month that the "Low Fuel" message comes on with about 4 gallons remaining in the tank. ?So 26 to fill up from that point sounds right given we have 31 gallon tanks (1500 trucks).

goo929
 
Ok I am going to try the MMO. thanks. Just FYI with only 700 miles, my AV gets better milage than my wifes 96 Ford Windstar 3.8. I must admit that 3.8 v-6 is about the only thing that van has going for it. I will report my MPG.
 
:D: Tank before last one got 10 MPG all city, the last tank got 8.8 all city with a couple of, put the peddle to the metal just for fun. Just love a V8's sound at full throttle. :B:
 
First four fill ups

10.0
10.6
10.1 first three all in town
11.97 about 50/50 highway town

Our terrain around here is all up and down hills not much level ground.

2500 w/8.1 & 4.10's
 
Hey bfron, I guess we're doing something wrong.
Boar-Ral is saying that he's getting 21H/19C. (first trip on mobil 1 thread)
The only way I can see that good of mileage is driving all down hill.
Even with mine set on 65 on a flat road with no headwind I only got 16. I wish I could get some of this magic gas and oil some people are using. The best I get in town is 14.
I think I'm going to rig a sail on my roof rack and just tack from one side of the highway to the other.
 
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