going up in tire size

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429
Location
US
hey, I got a 89 chevy 3/4 ton that has stock 245/75/16 I want to move up to 265/75/16 tires. Am i going to lose mpg and will that small of a difference cuase braking gear problems?
 
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843
Location
Grove City, OH
Keep the stock tire size. First off, example, your speedo might say 65mph and you might really be doing 69 with that taller tire. Trust me, this alone is not worth it. No one but you will give a hoot about its stance with wide tires. With the taller (and heavier) tires gearing will change and slow the truck down i.e. 0-60. Fuel mileage will go down due to more rolling resistance.
 
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1,397
Location
Katy, Texas
quote:
Originally posted by goodoleboy: hey, I got a 89 chevy 3/4 ton that has stock 245/75/16 I want to move up to 265/75/16 tires. Am i going to lose mpg and will that small of a difference cuase braking gear problems?
If you want to upsize without screwing up anything major like the speedo or having to change gearing.... P255/70R16. That's a size that is about the same diameter as the tires currently on your truck. 265/75R16 is about an inch or 2 taller.
 
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1,397
Location
Katy, Texas
quote:
Originally posted by Eiron: According to this Tire Size Calculator the 265/70-16s are the closest size match to your 245/75-16s. Tire Rack came up with 44 models of truck tires in that size. [Cheers!] Just out of curiosity, why do you want to change sizes?
Whoops. Well. the 265s are slightly taller (not enough to worry) and the 255s are slightly shorter (again, not enough to worry).
 

goodoleboy

Thread starter
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429
Location
US
The reason i want to change size is for ground clearance and look. mostly ground clearance though.
 
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4,844
Location
Saskatchewan
The 265/75's will be 3.9% bigger. So when your speedo reads 65mph you'll actually be going 68mph. 265/70's are only 0.5% bigger, so they wouldn't give you much extra clearance. You'll lose a little mileage on the wider tires, but gain a little by making the gearing a little taller. Probably not enough either way to be of concern. There will be no significant effect to braking, and the you'll probably be 0.1 or 0.2 seconds slower on your 0-60 time, which is probably over 10 seconds anyway.
 
Don't forget going to a larger diameter tire will cause alignment problems, figure a 4 wheel if it's possible or at least a two wheel alignment into the cost picture. Sometimes the alignment can't be done without buying some aftermarket parts due to the stock parts not willing to fit the larger wheels and tires, which can add more to the big picture. Just some food for thought! Good luck and let us know what you decide and how it all went. [Cheers!]
 
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1,397
Location
Katy, Texas
quote:
Originally posted by Steel Blue Wind Rider: Don't forget going to a larger diameter tire will cause alignment problems, figure a 4 wheel if it's possible or at least a two wheel alignment into the cost picture. Sometimes the alignment can't be done without buying some aftermarket parts due to the stock parts not willing to fit the larger wheels and tires, which can add more to the big picture. Just some food for thought! Good luck and let us know what you decide and how it all went. [Cheers!]
Explain. I have slightly bigger tire...I've never heard this one before.
 
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4,844
Location
Saskatchewan
quote:
Originally posted by JeepZJ4.0: Explain. I have slightly bigger tire...I've never heard this one before.
If true, I'd think it only applies to drastic changes in tire size. I've never heard of alignment issues when upsizing. Probably not a bad idea to get an alignment with new tires anyway though.
 
Messages
1,397
Location
Katy, Texas
quote:
Originally posted by rpn453:
quote:
Originally posted by JeepZJ4.0: Explain. I have slightly bigger tire...I've never heard this one before.
If true, I'd think it only applies to drastic changes in tire size. I've never heard of alignment issues when upsizing. Probably not a bad idea to get an alignment with new tires anyway though.

Too bad I've put 20K miles on the Yokos. The Jeep has a natural tendency to wear to the outside on soft compound tires and its just magnified. At 10K miles, I had my tire shop unmount them and remount them so the part that had lots of tread could get some exposure. It seems to be working quite well. I'll probably get another 15K out of them. My dad knows we messed up by not getting an alighment.
 
Messages
243
Location
PA
Go for it. Heck I'm runnin 265/75/16s (stock are 265/70/16s) on my 4cyl Tacoma 4x4 without difficulty. Only lost 1-2 mpg depending how I drive. I didn't get an alignment and they are wearing just fine. Course I rotate em every 6k.
 
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