tire tread type and FE
 

My 99 Silverado 5.3L (hardly a gas saver) came with Off Road tires on it. They are loud and vibrate alot. I figure they certainly cannot be helping my FE.

Does anyone know if a Highway tread would help FE much.

for the record
I currently get 15-17mpg.

Absolutely. In my previous Honda, I saw fuel economy differences of 5% - 13% among various highway tires, which meant some had lower rolling resistance than others. So if you go from an off road tire, which is almost certainly not a low rolling resistance (LRR) tire, to a highway tire, you should see significant FE improvements. And if you specifically select a LRR highway tire, the improvement should be even more substantial.

Check out the Nokian WRSUV to see if it's available in your tire size:
https://www.nokiantires.com/en/tire_w...?season=summer

It's a LRR tire. I went through 2 sets of Nokians on my previous Honda (not the WR). Great handling, long tread life, LRR. Best tires I ever used. If you buy the Nokians and inflate them to the maximum sidewall pressure (likely 44 psi), I'll bet you'll get 15%+ better FE than you are now.

The BFGoodrich Long Trail has a low rolling resistance and not very agressive tread. I'm pretty sure the greenseal.org report lists it as doing well. Do a search for 'LRR tires' to find it.

Michelins...XGT I think

I'd go with a Highway All-Season tire on a Silverado. Like beatr911 mentioned, the BFG Long Trails are pretty nice. I had them on my old S-10 p/u. They did loose traction rapidly when I was down to 5/32nds, however. The Yokohama Geolander H/T-S G051s are another nice choice, IMO. You may not be able to reap the full benefits that a passenger car would w/LRR tires....but its a good start!

LRR tires is a good start. but,even @ 5 or 10% gain, you won't see much in your FE w/ that vehicle.
look in the archives for truck threads. grill block, airtabs,driving techniques, etc will help you as well.

I put narrower tires on my F350, and it seemed to help about 1 mpg or so. The original tires were 265 75R16 BFG Long Trail. The new tires are Michelin 235-85R16 M&S tires. The new tires are a tad taller, just 0.3". They don't have a very aggressive tread, but they did well last winter. Never got stuck.

I'm going to northern Maine next week, off road. I hope they do OK on muddy and snowy dirt roads.

The knobby off-roaders generally have a high resistance. Comsumer Reports has the latest report on tire RR, but you have to pay to use it.

I have Michelin MXV-4 "Green-X" LRR treads on the 'Teg. Overpressure and this tread design really helped boost FE. Judging from my Gaslogs, I would say that it helped in the 5-10% range, plus or minus. They're a bit pricey, but I don't worry so much putting 50 psi in them. One-year of use and they're great.

Best FE...

RH77

glad i didn't mention acetone. <looks around for flying rocks>

anyway, there are things in addition to driver mods that MAY help.

as previously stated, "if something works for you continue using it, if not then stop."

never tested them. but, i can SHOW you that acetone,for example, DOES(my car) and DOES NOT work(wife's car). if you don't come see it, you'll have to take my word(tested #s)for it. or not, the choice is yours.

i understand your skepticism tho. i'm a "seeing is believing" kinda guy.

BUT, remember...don't believe anything ya hear, and only half of what ya see!