couple of proven facts
E85 decreases mileage from 15.4 to about 12.5
E10 is better to use than E85
also E85 decreases engine longevity (GM won't care - you'll just by a new engine / vehicle quicker)
try this:
3 oz PURE Acetone (found at Sallys Beauty Supply)
3 oz Xylene (found at most hardware stores)
1 oz 5W40 Synthetic oil
---> per 10 gallons of 87 Octane (NO Ethanol !!!!)
get you a funnel - acetone removes paint - ask your female partner - that's what they use to remove fingernail polish
you should see an instant 10% mileage increase and a power boost - your truck will think it's running on 93 Octane
depending on your computer in your truck it might try to adjust the increased mileage back down.
Careful with that mixture, theres another proven fact that an Acetone/Xylene mix is highly volatile and has a probability of spontainously combusting. Also acetone has been known to damage plastic fuel tanks, "O" rings in the fuel system, and rubber fuel hoses (which many vehicles have now a days).
The best method for good fuel mileage on your Suburban is:
1. Dont carry lots of excess heavy items inside, keep the vehicle weight down (extra add ons like brush guards and nerf bars not only create wind resistance but also add weight).
2. Ensure your tires are properly inflated. Draw a chalk line on the ground in front of each tire, roll the truck across the line then check the tires, you should have a chalk line across the tire now. If you have chock only on the outsides the tires need more air, if you have chock only on the center the tires are over inflated.
3. Get a tune-up and clean the injectors and intake.
4. Get a quality air filter (My preference is dryflow filters).
5. Drive with a light foot.
6. Some tests have shown ensuring the vehicle is properly warmed up before driving saves fuel also (I'm still not fully convinced on this one).
