I need new tires for my 1500 4x4 Ram and am looking for a quiet set, most likely A/S tires. I currently have OE 245/70-17 series on stock wheels.
The optional OE size is 265/70-17. What reason would I use the 265s... other than to spend more money?
Would 265/65-17 be an option?

 

bigger footprint = better traction

if i were you i would go with the 285/70-17

 

Would 285 throw off the speedo much?

 

i think its like 4mph difference but if you have a tuner you can change the settings to correct your speedo when i had my old chevy truck i just would keep in the back of my mind hey im actually going 4mph faster than what this says

 

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.

 

i have 285/70/17's on my 2003 1500 4x4 hemi and im off 9mph when my speedo is at 65, but there supposed to be 265's and i have really agressive Cooper discoverer's which is prolly why its so bad

 

Aggressiveness has nothing to do with the speedo reading, just tire diameter, or more specifically the circumference of the tire.

Doing the math, going from a 265/70/17 tire to a 285/70/17 tire will result in a 1.2 mph difference at 65 mph. If you have a 9 mph difference then the laws of physics cease to exist around your truck, LOL...

 

I agree, go with a 285/70/17, 245 looks horrid and a 265 isnt much better. Just stick with something that isnt super aggressive and you should be fine and not lose too much.

The Nitto Terra Grapplers are a great tire in that size and you can usually find them for around $185 a tire.

 

I guess my truck doesn't apply to the laws of physics then cuz I a ticket last week for going 74 when my cruise was set on 65 and I got new tires the week before.... doing the math doesn't always mean ur right lol

 

I'd suggest take a GPS out and verify your speedo, might be it'll get you out of a ticket. I worked in the technology end of law enforcement and have seen radar guns off by quite a bit. In my state, if the gun has not been certified within a certain time period, the reading must be thrown out in court. Many PDs don't certify on time and rely on people not bothering to fight the ticket.

I've GPS checked MANY tires vs. speedos over the last 15 years or so and I've NEVER seen one off by 9 MPH and that's with 38" tires!

The math works, EVERY TIME...

I'm running 32.5" tires on my Grand Cherokee, NO SPEEDO RECALIBRATION and stock tire size is 29.5" and I'm off 3 MPH at 65. Prior to tuning my truck, with 35" tires (stock is figured at 32.5") my speedo was off 3.5 mph at 65 GPS VERIFIED!!!