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Discussion Starter #1
So I was thinking about this the other day that I drive ALOT of highway miles and only a few city, maybe 80/20. Right now I have the stock 265s on there and I was thinking about 315s. Wouldn't my mileage actually benefit from the bigger tires because my engine would run at less RPMs on the highway. Now, I know I'd take a hit in the city, but if i was easy on the pedal and just got it moving slowly then it would work to my advantage. Anyone have any experience or thoughts??
 

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Tiger, what kind of mileage are you getting now? I have 315's on my truck and can tell a difference as far as lower rpm's higher speed. Rolling down the highway at 1750 rpms my truck gets extremely good mileage. I don't have an overhead so I can't tell you an exact number, but I got put fuel in my truck when it got down to 1/8th tank after 615 miles. Not too bad.. Plus bigger tires look way better and you can run over civic's and stuff. Hope this helps!
 

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Yeah...big tires and runnin over stuff!
 

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Discussion Starter #4
I've been getting about 15.5mpg right now, but I just put a Quadzilla M3 on this tank so we'll see how it changes. The overhead already reads 18 and it was pretty close to accurate before, but I've heard the M3 can play major games with the overhead. We'll see when I get to hand calculate it.
 

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I'm thinking the 315's are a damn worthy investment. Which tires were you looking at? Tell me how you like the m3.
 

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Discussion Starter #6 (Edited)
It's either 315s or a motorcycle cause either one is an investment for mileage as stupid as that sounds. I like the BFG All-terrians as I wouldn't be running off road too often except to play around, but not planning on testing myself in any mud. I'll let you know about the M3.
 

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I hear you on the motorcycle man. I've been wanting one really bad lately for that exact same reason. If I had 5k stacked I'd buy one tomorrow!
 

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It's either 315s or a motorcycle cause either one is an investment for mileage as stupid as that sounds. I like the BFG All-terrians as I wouldn't be running off road too often except to play around, but not planning on testing myself in any mud. I'll let you know about the M3.
If you are expecting much of a mpg gain with tires, buy a motorcycle.

The 315's are beyond the optimal size for mileage. Too much weight and foot print to gain much alone. Anything beyond a 285 is gonna start robbing mileage with the width, taller than 33" and the weight gets to be the problem.

FYI, while the BFG's are cheaper they are a major cause of death wobble and generally wear screwy. If you invest in tires Toyo AT's or MT's are still the best around.

My experiences and .02 :thumbsup
 

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For as much highway as you're driving, I'd say go with Michelin LTX AT2s 285/70. You'll get to wait 80K instead of 40K before dropping another $1200 on tires. Plus, the ride can't be beat.
 

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the added height might reduce your RPM's, but the increased footprint and weight will offset it.

Going larger rarely increases milage.
 

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You will lose1 1/2 to 2 mpg gallon going to 315's. The added weight & footprint on the ground will overide any rpm advantage.
 

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i have a 07 maga cab 4x4 like to get more of a mud tire on stock rims how big can i go on a dually. with 235/80/17 stock
 

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If you are expecting much of a mpg gain with tires, buy a motorcycle.

The 315's are beyond the optimal size for mileage. Too much weight and foot print to gain much alone. Anything beyond a 285 is gonna start robbing mileage with the width, taller than 33" and the weight gets to be the problem.

FYI, while the BFG's are cheaper they are a major cause of death wobble and generally wear screwy. If you invest in tires Toyo AT's or MT's are still the best around.

My experiences and .02 :thumbsup
Ditto. Well put! I went with a compromise on the '07. 285-75-17 Toyo AT's. 34 x 11.50 x 17.
 

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You will lose1 1/2 to 2 mpg gallon going to 315's. The added weight & footprint on the ground will overide any rpm advantage.
I agree, I lost probably 1 mpg. Running easy 65-70 for 425 miles I got 19.4ish, always hand calculated, never use overhead.
 
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