Is 20MPG possible

[dcarver]

So I'm trying to reach my goal of 20MPG from my 03 Suburban. I would like 20mpg because my parents live 530 miles away and really i think it would be fun to make it on 1 tank of gas.
Currently getting 18MPG driving 75mph (speed limit in TX).
I have no mods except a flat K&N filter from PO.
Besides obviously slowing down (which won't happen with 530 miles to drive), will these mods give me my goal?

Replace stock intake tube with spectre tube from Oreilly's and do the cheese grate mod to filter box
Free flow muffler, or should I do Cat back?
And finally a tune or are these even enough mods to warrant a tune?

BTW I have used the search function but I couldn't tell if others asking the same question were just looking for a couple mpgs or 10. Also I know 18mpg right now is pretty good seeing what others have said in different threads but heck, can't hurt to ask right?

Thanks for the help!

 

[Gzes]

wish speed limit was higher up here. believe below austin the got a 80-85 mph speed limit. love how when you cross into ok it goes from 75 to 70.. last time i went to ok i was going 90 in a convoy with my tow dolly in the back lol

 

[BirchyBoy]

An important factor in MPG is tire inflation. Do you check your pressures before leaving?

 

[livingez_123]

18-19 is fairly common 20+ your going to have to work a bit harder. anything over 65mph kills the MPG. It will come down to driving style.

 

[Goodinblack]

Yes...... very possible. You just have to drive like 50 MPH all the time. Inflate tires to max psi. Light throttle.

 

[dcarver]

haha ya i can't remember what road it is in Austin where the speed limit is 85 but i was getting passed doing 90 lol. Also I10 has an 80mph spred limit and we drive that to my parents as well.
I do check tire inflation regularly with Lubbock weather going from 0 degrees to 70 in a day lol.
I'm looking at buying some LT tires so i can run 75psi instead of 40psi with the tires I have now.
I also try and not use the cruise when going up the big hills around Junction TX but I usually dont dip below 55mph

 

[Goodinblack]

Overinflated underloaded tires will wear the center out fast. Cost of new tires negates the fuel savings.

 

[dcarver]

Overinflated underloaded tires will wear the center out fast. Cost of new tires negates the fuel savings.

I did not know that. Thanks for the info!

 

[YukonXL04]

I have the same air filter as you, and a borla muffler, DIY intake tube, and getting my BB tune on Friday. Hoping that's helps some. Also I plan to do electric fans after the tune sometime. So after that I will be curious what my mpg will be after all that. With my driving habits I'm in the 16-17 range with mostly city/ stop and go traffic. So hopefully will see some kind of increase. However once you put a muffler on you tend to give more throttle to hear it lol

 

[Gzes]

wow i10 is down there.. i take 82 to lubbock about 3 hrs for me at the speed limit lol..