Buying new 17" tires - 245 or 265?
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OP I went from 245's to 265's on my 2wd and liked the increase in traction of the wider tire. Like Hammer said you may lose 1 mpg for the taller and wider tire, whether that and the slightly higher price of the tire is worth it is up to you.
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I am taking my family on a 3000 mile road trip soon and the tires i have now are approaching 7 years old and have 37k on them (original tires). They have legal tread but I figured I should replace them on age alone.
If I go from 245s to 285s, according to one calculator, the speedo will read 65.28mph, and the actual speed will be 70mph. That's a big difference for a mild freeway speeder. That is a concern for me.
What is the cost to calibrate?
Will they fit well on the stock 17x8 rims?
Thanks for your input.
If I go from 245s to 285s, according to one calculator, the speedo will read 65.28mph, and the actual speed will be 70mph. That's a big difference for a mild freeway speeder. That is a concern for me.
What is the cost to calibrate?
Will they fit well on the stock 17x8 rims?
Thanks for your input.
Last edited by 2005DodgeRamDad; Jun 3, 2011 at 05:08 PM.
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Yea sounds like your tires are getting old and it's smart move to replace them. The 285's should fit on stock rims and I think the dealer charges something like $80 to recalibrate for the different size. If you're interested in a tuner for your truck some of them allow you to change tire size, but they cost more than $80.
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I am taking my family on a 3000 mile road trip soon and the tires i have now are approaching 7 years old and have 37k on them (original tires). They have legal tread but I figured I should replace them on age alone.
If I go from 245s to 285s, according to one calculator, at 65.28mph, the odometer will read 70mph. That's a big difference for a mild freeway speeder. That is a concern for me.
What is the cost to calibrate?
Will they fit well on the stock 17x8 rims?
Thanks for your input.
If I go from 245s to 285s, according to one calculator, at 65.28mph, the odometer will read 70mph. That's a big difference for a mild freeway speeder. That is a concern for me.
What is the cost to calibrate?
Will they fit well on the stock 17x8 rims?
Thanks for your input.
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From: South Georgia/East Florida
Rule of thumb for tire fitment is the tire ideally should be 3" wider than the wheel with a -/+ 1" considered within spec. So the 285/70/17s will be fine on an 8" wide wheel.
I know plenty of guys run a 12.5" wide tire on 8" wheels and as long as they don't air 'em down for off-road, nobody has reported a bead separation...
I know plenty of guys run a 12.5" wide tire on 8" wheels and as long as they don't air 'em down for off-road, nobody has reported a bead separation...
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The 245/70/17 is a 30.5"x9.5" tire. A bit puny for a full size truck in my opinion. Hell, I have 265/70/17s on my soccer mom'ish SUV.
The 265/70/17s would be almost exactly 1" taller and 1" wider at 32.4" x 10.6". Where a 285/70/17 tire would be just a hair under 33" tall and 11.5" wide.
Yes, the speedo will be off when changing tire size. The speedo is calibrated for the tire size listed on the door (which might actually be 265/70/17 as this is what's on my door, so your speedo might be off right now with your 245/70/17s). Adjusting speedo is an easy step that your dealer can do with the ScanTool or you could do with a programmer/tuner.
As far as running different size tires, as a general rule, the wider a tire, the larger the surface patch or footprint it puts down and better traction. The taller the tire, the more ground clearance. Plus, big meats just look cool.
The down side to taller and wider tires is they cost you fuel economy. Figure about 1 mpg loss for every inch you go taller and about 1 mpg loss for every inch you go wider. Other variables like aggressiveness of the tread comes in to play as well.
The 265/70/17s would be almost exactly 1" taller and 1" wider at 32.4" x 10.6". Where a 285/70/17 tire would be just a hair under 33" tall and 11.5" wide.
Yes, the speedo will be off when changing tire size. The speedo is calibrated for the tire size listed on the door (which might actually be 265/70/17 as this is what's on my door, so your speedo might be off right now with your 245/70/17s). Adjusting speedo is an easy step that your dealer can do with the ScanTool or you could do with a programmer/tuner.
As far as running different size tires, as a general rule, the wider a tire, the larger the surface patch or footprint it puts down and better traction. The taller the tire, the more ground clearance. Plus, big meats just look cool.
The down side to taller and wider tires is they cost you fuel economy. Figure about 1 mpg loss for every inch you go taller and about 1 mpg loss for every inch you go wider. Other variables like aggressiveness of the tread comes in to play as well.
As much as I would like bigger tires, The extra cost of the tires plus calibration at the dealer plus less mpg might not be worth it... bummer.
The door sticker does say 245's.
I am leaning towards purchasing Michelin LTX M/S2.
Last edited by 2005DodgeRamDad; Jun 3, 2011 at 10:58 PM.
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I'm a big fan of bigger wider tires, don't cheap out too much on tires. I was driving my dad's truck through some light mud at the junkyard and got stuck in 4wd with crappy 265 A/T's where I normally idle along in my 305's in 2wd.
IMO the mileage dip is worth it! I also run 285's in the winter, it's a good width for winter tires
IMO the mileage dip is worth it! I also run 285's in the winter, it's a good width for winter tires
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From: South Georgia/East Florida
I agree that a bigger tire would look better but the mpg issue you mention is food for thought. I barely eek out 13mpg so I do want 1 or 2 mpg worse.
As much as I would like bigger tires, The extra cost of the tires plus calibration at the dealer plus less mpg might not be worth it... bummer.
The door sticker does say 245's.
I am leaning towards purchasing Michelin LTX M/S2.
As much as I would like bigger tires, The extra cost of the tires plus calibration at the dealer plus less mpg might not be worth it... bummer.
The door sticker does say 245's.
I am leaning towards purchasing Michelin LTX M/S2.
The Michelin LTX line is an excellent line of road tires, btw.
Some dealers will flash the speedo for free, especially if taken where the truck was purchased, some charge up to an hour labor (it's really about 5 mins with the ScanTool and can be done in the parking lot).
Last edited by HammerZ71; Jun 3, 2011 at 11:16 PM.
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I guess I am trying to balance out needs vs. wants. My 4x4 Ram is basically a four door car with a big trunk to haul the wife, kids groceries and seasonal sports equipment.
Not more than a few days of snow in the Seattle area.
Not more than a few days of snow in the Seattle area.
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Yeah, I had 4x4 specs in my head, the 4x2s are based off a 245.
The Michelin LTX line is an excellent line of road tires, btw.
Some dealers will flash the speedo for free, especially if taken where the truck was purchased, some charge up to an hour labor (it's really about 5 mins with the ScanTool and can be done in the parking lot).
The Michelin LTX line is an excellent line of road tires, btw.
Some dealers will flash the speedo for free, especially if taken where the truck was purchased, some charge up to an hour labor (it's really about 5 mins with the ScanTool and can be done in the parking lot).
Quite a bit more for a taller look (which I like) but less mpg.
I guess I am being practical with two kids in high school that like to play band and sports.
That means their priorities and not mine. Good Dad!
I should call the dealer in the morning to ask about flashing the speedo... just tell them I may change tire size to get a quote for it?