We just got back from a 500mile(one way) trip doing between 70-75mph and averaged a little over 21mpg in our 96 Blazer with 168K miles.
I'm happy about that!

Can't wait till I get this thing running in tip-top shape.

Congrats man...my 97 gets about 20....and has gotten as good as 22.3 for 1 tank...lol....that's pretty good IMO.

21 MPG is pretty impressive for a 4x4 Blazer. Most I have ever heard of was 17- 19 mpg. My 2dr is getting 24 mpg.

That is impressive.
The best my 95 LS 4x4 has done is 16.4 mpg, this last tank as a matter of fact.I don't think there is any way possible for me to squeeze another 4mpg out of this old girl.
She is in a good state of tune,Good stock tires and bumped up pressures,fresh fluids and filters,good coat of wax she gets what she gets!!!

jezz im getting 16.8 per tank
whats the best way to improve that?

this would be all highway driving that he got 21-22mpg on. I have gotten 24-25 doing 60 on state highways (speedlimit 55mph) I have never gotten close to that again, on the highway i tend to average about 18-20mpg which is good enough. There are lots of variances in peoples vehicles when they are brand new let alone at that kind of mileage. A lot of the mileage depends on the drivers right foot, what gears and what not are on the truck, what size tire/type of tire (stock size vs. 30-33's and highway allseason vs. AT/MT), and weather too. There are threads on this subject already so i suggest using the search function and search for "MPG's" or "gas mileage" or "mileage improvements" that should get you somewhere.

My record high was 24MPG.

But that was before the brush guard, extra lights, and 30" tires :D

That was at 75 MPH the whole way.

not bad, i just went skiing at snowshoe in west virginia and through the mountains i achieved exactly 20 mpg. on the highway i usually get between 22 and 23 with a best of 25. but i like to feather the throttle unless im messing around, and i drive a constant speed the whole way through. Also when i hit a hill i try not to let the tranny go out of over drive. i just move into the right lane and not worry if my speed goes down a little. as long as im not bothering anyone of course.

Yep thats how I pulled 25mpg off before.

cool deal.

The best I've gotten out of mine so far is 22