So recently I have tried a few things and they have helped immensely. First I started using cruise control and it went up a little bit. The next tank I put in seafoam, half a bottle into my gas tank to clean out the crap and I skyrocketed from about 25-26mpg to 29mpg. I would of gotten better but the day I was going to fill up I got stuck in horrible traffic. Then this last tanke I hit 28.6 and I was little throttle happy this tank to. Needless to say I have consistently upped my mpg by a good bit.

BTW I say 2-3 because randomly I would get 27 but not very often.

 

Putting a header on greatly increased my highway MPG's. With CAI, Header and axle back, I get around 33mpg highway.

 

seafoam? Fuel injector cleaner/additive?

 

http://www.seafoamsales.com/
It help remove carbon build up in your engine.

 

I plan on doing oil soon along with some through the intake. Intake gotta be careful.

 

What type of driving do you do most? I know my city/highway MPG average is around 24.5 but when I'm on the highway for extended trips, I have hit 31.5 consistently.

 

Seafoam Motor Treatment is great for cleaning out an older engine's intake, valves, and cylinders. Burns off the carbon deposits and other garbage. Questions have been raised about it's impact on rubber hoses (due to the small alcohol content), but another product that also does a great job on cleaning the fuel system and extending MPG is MMO (Marvel Mystery Oil). It's also very effective as an oil additive.

 

Mostly highway, but I live in the country and our highway has a lot of steep hills. The very first thing I do when I get on the highway is go up a high about a mile high.

 

Mobil 1 0-20 also made a significant difference in how the engine felt at around 70mph in my xb.

 

Seafoam - does it actually do anything? Or are your mileage improvements based on erroneous data? Not blaming anyone, but in my case there have been times when I didn't get the tank full for unknown reasons, and that throws off the mpg calc. There is a lot of variability with just one reading.

 

Are you guys going by the bogus numbers on the dash or doing the math at full up? I've NEVER gotten over 29 mpg, and I drive almost all highway at 68 mph ( 30 mile commute to work each way ).

Also I would like to add that most filling stations in the north are now switching from winter blend to summer blend fuel so you will see a jump in mileage due to that as well. My winter mileage averages 24-26 and summer its usually a solid 27

 

Doing 68mph doesnt help either. I do around 60ish on the highway and I don't go by the calculator on the dash its all done by hand

 

i just started getting the 350 range. that the cars digital display shows.

 

Quick question. I know what CAI is and headers as well. But, when you talk about axle back, are you talking about the exhaust?

 

Oh, another thing. The shop that does my scheduled maintenance wants to sell me a fuel system cleaning. Should I buy into it or would a simple can of Sea Foam do the trick?

My XB is at 30,000 now.

 

My MPG finally start going back up after using the most terrible winter gas ever, seriously, I never got so bad since I have owned the car since 2007 like this winter. Thankfully, they must of just switched back to summer blend because my mpg is back up to 28-29 from 25. I also threw in some redline fuel additive and techron additive a few weeks after to give a nice little cleaning to the fuel system. Oh, and my spring oil change with 0W20. Nice to have my MPG back, though... It is not unusual for me to average 28-32 every tank in summer. If my current tires get replaced before seasons end, they will also be replaced with more low resistant, fuel efficient tires versus the Falken 912's I have on now... So that may also increase my mileage even more, which I am happy about.

 

They are trying to scam you bro, at 30k that ain't needed AT ALL. Seafoam it if you want to feel better, but your fuel system is fine. Unless your running E85

 

My middle Brother in law ran a Marina shop for years. He turned me onto Seafoam. Works great for cleaning the fuel system. I know on my 1st Gen Box I can put a whole can in on fillup and pick up 3 MPG. This works everytime. I haven't tried it yet on my 2nd Gen Box. Will have to try it next road trip to south Georgia.