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Discussion Starter · #1 ·
I am about to change my All season tires. I want to know how would the width of the tires affect the performance of my nox. Also will there be any change in mileage if i install wider tires?

I currently have GENERAL Grabber P235/65R16.

I was looking at Bridgestone P235/75R16 or something like that. ;D
 

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Are you wanting wider tires or taller tires...your post confuses me. P235/65R16 and P235/75R16 are going to have the same tread width...but the 75R16 will have a taller sidewall.

If I understand tire sizes correctly.."P235/65R16" means this..

"P" is for passenger car/truck
"235" is the tread cross section in milimeters
"65" is the sidewall height in millimeters
"R" is for radial
"16" is the size wheel that it fits in inches

And to answer your other question, yes wider and/or taller tires can have an effect on your mileage...but it all depends on how radical the difference is from stock.
 

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Discussion Starter · #3 ·
hmmm.... I am confused too,, the guy at costco said that when I said that I want wider tires.
 

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arvindh said:
I am about to change my All season tires. I want to know how would the width of the tires affect the performance of my nox. Also will there be any change in mileage if i install wider tires?

I currently have GENERAL Grabber P235/65R16.

I was looking at Bridgestone P235/75R16 or something like that. ;D
75R/16 is not the way to go, - by doing so will increase your overall diameter from 28.02"(711.7mm) to 29.87"(758.9mm).
Which is a 6% increase in diameter - which is over the safe limit of 3%, some tire shops won't change this over for you as going over a 3% increase in factory diameter may cause brake failure.

The other perspective is, if your actual speed is 60mph, your speedo will only show 56mph (it's 6.6% out)
Stick to the 65R16, if you want wider, get your tire shop to fit you one.

The cross section and the sidewall height are directly related to each other. If you change one value it changes the other.
For example, you want wider so you pick a 245/65R16 - even though the cross section increases the diameter differs also by 0.5"(12.96mm)

Your tire shop will find you a wider tire that will be really close to the original diameter so that everything works perfectly.[/color]
 

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A 255/60-16 is just a tad larger in diameter than 235/65-16. This tire would be 20 mm wider.


Mulitiply the old 235 by 65 and you get 152.75 mm
Multiply the new 255 by 60 and you get 153 mm
 

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Discussion Starter · #6 ·
X11Fan said:
A 255/60-16 is just a tad larger in diameter than 235/65-16. This tire would be 20 mm wider.

Multiply the old 235 by 65 and you get 152.75 mm
Multiply the new 255 by 60 and you get 153 mm
Thanks X11Fan. Any idea on how the mileage would be affected?
 

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arvindh said:
Thanks X11Fan. Any idea on how the mileage would be affected?
in general terms...

wider tread = more surface contact = more effort required to roll the mass = more fuel needed = worse mpg
 

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Discussion Starter · #8 ·
MOCHANOX said:
wider tread = more surface contact = more effort required to roll the mass = more fuel needed = worse mpg
Bummer...well as long as I dont take a huge hit on mileage, I am fine.
 

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noxguynf said:
Bummer...well as long as I dont take a huge hit on mileage, I am fine.
Your size change is probably insignificant in terms of MPG. Probably the tire brand, tire material and tread pattern will have a bigger impact.
 

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noxguynf said:
Bummer...well as long as I dont take a huge hit on mileage, I am fine.
Like I said, the hit you take will depend on how radical you go. If you intend to go significantly wider then you'll have to go with a wider wheel as well...and any changes you make versus stock will have some effect on ride quality/handling/fuel mileage, but how large or small is up to you.
 

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Discussion Starter · #11 ·
i hope costco has a return policy for wide tires then.. :D
 

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