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Mpg questions with lift, wheels,tires


Sierrasle

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Posted

I have a 2015 GMC Sierra 1500 and I am planning on a zone 4.5 lift kit with 275/65r18 and 18x9 fuel maverick. Mpg is a big thing to me since I do all highway driving and was wondering how much mpg I will lose after the lift and bigger tires. Stock was 255/70r17. It's my first time on a forum, I will greatly appreciate whoever helps me out!

Posted

Welcome! Use the search feature and you will find a great deal of discussion on MPG with lifts, levels and larger tires. I think you will find a wide range of answers! The most significant factor, I believe, is the type of tire you choose. The size you are suggesting is pretty close to stock. If you choose a highway tire, the impact on MPG wouldn't be as noticeable as switching to an AT or MT tire. You are going from an overall wheel diameter of 31.1" to 32.1". The 1500's with the factory 18's have a diameter of 31.6" and 20's have a diameter of 31.9".

Posted

Mpg is a big thing to me since I do all highway driving​.

 

Must not be very important or you would not be doing any mods. :happysad:

  • 3 weeks later...
Posted

275/65/18 is a very conservative size for a leveled truck, let alone a truck with a 4.5" lift. MPG will probably drop 2-3 from completely stock, depending on your driving habits.

Posted

275/65/18 is a very conservative size for a leveled truck, let alone a truck with a 4.5" lift. MPG will probably drop 2-3 from completely stock, depending on your driving habits.

 

I share this opinion.

Posted

I have a 2015 GMC Sierra 1500 and I am planning on a zone 4.5 lift kit with 275/65r18 and 18x9 fuel maverick. Mpg is a big thing to me since I do all highway driving and was wondering how much mpg I will lose after the lift and bigger tires. Stock was 255/70r17. It's my first time on a forum, I will greatly appreciate whoever helps me out!

the 275 6518 (32.1) is a small tire for a 4.5" lift want be much different then stock if you really wanna keep the MPGs go with a 20 wheel and get a p rated tire 275 60 20 is a 33 vs a 32 and it the same width the reason a say 20" wheel is there more opinions in p rated tires there are a few p rated 275 70 18 witch is a 33.2 but nothing aggressive the more aggressive the less the mpg and the more the tire weighs is a factor to I have a 3 inch lift with stock 265 65 18 still get 20 mpg with the 6.2 I'm going to go with 265 70 18 ( around 45 lbs ) p ratted witch is a 32.6 or LT 275 70 18 ( around 55 lbs ) witch is a 33.2 but much heavier tire if you that worried about mpgs id do a 3 " lift with 265 70 18 like myself hope this helps you some but it really comes down to what you want out of the truck looks or mpgs there not much happy medium when you start going big

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