The Mother of all gas mileage tests....

...sorta. More like the semi-definitive/your results may vary/it worked for me/not exactly scientific, old guy's observations on fuel consumption under the following conditions:

the ride: 06, v6, auto, K&N drop in, Gibson cat back.

the driver: old but not slow, not usually in a hurry but drive with a purpose, don't really care how fast you can pass me, do nail it thru a couple of gears on a regular basis.

the route: mostly rural roads and state hiways, in and out of town every day, not many stop lights. No city driving and maybe 50 miles a tank on the hiway.

the conditions: 5000'+, not many flat roads around, midrange octane = 87, hi test octane = 91, AC on when needed (most afternoons), I generally let the trans shift between 2,000 & 2500 rpm, no cruise control, regular fuel..no oxygenated (oxy-junk) fuel.

the quest: salesman said 'put reglar in her grandpa', book said midrange (with hi test for 'added' performance), Service manager said computer not that smart...mid range. So..does Hi test make a difference?

the test: 3 tanks of mid range; 3 tanks of hi test (and a tank of 93 octane at the end...scarce and pricey.....just for shitsNgrins). Same station/brand for each.

the results: mid range averaged 19.5 (19.2, 19.9, 19.5) give or take a tenth. hi test averaged 20.0 (19.9, 20.0, 20.2) give or take a tenth, 93 octane? save ur $$...19.5 (service manager partially right..computer not that smart).

observations: hi test did do better (if you get better mileage with a different octane, under similiar conditions...the motor's happier with that octane) The $$ are close to a wash...5 tenths better = 10 miles more per tank @ 20 gallon fill. At $3 a gallon that a buck 50; hi test here is 10 cents a gallon more or 2 bucks more a 20 gallon fill...your call. But I can think of a lot dumber ways to blow 50 cents. But then of course your results may vary.....


............geezer

 

Geezer, you have confirmed my earlier calculations I did on my '85 S-10. It had a 2.8 V6 and a 11 gallon tank, four speed (which needed a fifth). I had the same experience. No real change in cost but getting the extra mileage out of tankful on a long trip was worth it. Thanks for the update with a newer truck.

 

Good job on that test! Yeah, the V6 runs a bit better on mid-grade, but on the 2.7L it makes no difference.

 

Geezer what your low grade there? Here low is 87, mid=89, and high=92. I've used all three in my truck with no real difference so I stick with the 87.

 

TRD - We are blessed with 85 octane regular. Presumably, because of the altitude, we can get by with 2 points lower across the board. Actually it's a parts cleaner grade of gasolne. I treat my lower mowers, garden tractors, weed wackers and chain saws better than that. Why folks spend big $$ for a vehicle and run cheap gas and oil in it is waaayyy beyond me. But hey!! your results may vary.

................geezer

 

Hi All
I decided to get a laptop with wireless capability and take along with me on my travels and still keep intouch with the forum.
This thread caught my eye and since I am on the road doing my great adventure, I figure I would throw in my gas mileage numbers. On reg gas, Shell in particular, with a 4.0l auto drive, I average about 21mpg. On Hess, it drops down to 18 which I think is a significant drop. Mobile is about 19.3, same as with exxon. On another note is cost of fuel. New Jersey is $2.47 for reg, NY upstate is $2.89 unless your near a city where it goes to $2.97. Worst price is on Cape Cod, one particular gas station on rt 28 between Hyannis and Falmouth where it was $4.00 for reg. Obviously the gas station was empty of customers and I solely believe the owner was on Birdjuice.
The journey continues....................
I have also updated my truck with a A.R.E. Z series cap and step tubes from toyota which happen to match the silver paint almost perfect. Will take pics shortly and download them to here.

 

Glad to have you back sunruner, how have you been?

as far as the gas issue, i seem to get better mileage using 89 over 87 or 91. I have been using 89 for months now.