285s - MPG dropped... Normal?

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thinger2

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Most of you know that I went to 285s for the first time on my 97. It looks great, but, here's the kicker. I don't know if anyone has this much mpg loss, but when I got the truck with 265s, I was getting the same if not better than my 98. But since I went to 285s, mpg dropped... quite a bit. I just filled up Monday and have already sucked half a tank, this is a mix of town and highway driving.

Now, my 98 does the exact same mix of town and highway and I am getting 15 mpg with 4:10s! What gives? I know when going to 285s with 3:73s, the gear ratio goes to 3:42s, but is this normal mpg loss? I also know these trucks don't get the best mileage to begin with, but it should be getting better than this. I am about ready to sell my 285s and get the 265 version of these Dick Cepek's, because I do like the tire. I'm not sure if losing torque, and mpg was worth it for looks... Plus, the cruise control has a hard time as well.

I am going to be selling my PY0 rims off of my 98 because I got some polished 8 hole rims that finally fit, would it be a good idea to put the 285s and PY0 rims together to help sell better?

Edit: before my gas tank started leaking, I was only able to get around 170 miles out of the 97 (going from F to 1/4), whereas around 250 miles out of the 98 (going from F to 1/4).
Yep. I ran 285/75/16 Goodyear Duratracs on my 94 k2500 for the last couple of years. Finally couldn't take the howling any more so I just switched to 265/75/16 BFG All Terrain KOs
Much better mileage and a lot easier shifting.
And a whole lot less noise
 

alpinecrick

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Yep. I ran 285/75/16 Goodyear Duratracs on my 94 k2500 for the last couple of years. Finally couldn't take the howling any more so I just switched to 265/75/16 BFG All Terrain KOs
Much better mileage and a lot easier shifting.
And a whole lot less noise

And a longer life on steering, suspension and driveline components........
 

Supercharged111

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My Duratracs are nice and quiet, on my 2nd set now. They've only made noise when they cup, which only happens when the alignment is off.
 

98chevy2500SS

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Yep. I ran 285/75/16 Goodyear Duratracs on my 94 k2500 for the last couple of years. Finally couldn't take the howling any more so I just switched to 265/75/16 BFG All Terrain KOs
Much better mileage and a lot easier shifting.
And a whole lot less noise
That's exactly my plan when my 285s take a **** (kinda glad they are rated for 40-45k miles), gonna get some 265/75r16 BFG KO2's for it. I have always liked the BFG KO series tires, the price of them kinda scares my wallet though lol. Hopefully I will have enough money saved to get them in the future.

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Drove the truck some and got 86 miles on a quarter of a tank (filled clear full yesterday), so I will probably get more than 200 miles out of a full tank, which is around 12-13 mpg give or take, which is better than what I was getting! So I think my old gas tank was 75% of the problem (with it leaking), the other 25% being the tires and accessories.
 
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