# Tires



## z-family (Oct 2, 2004)




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## DernMooseAK (Apr 16, 2004)

If you got those 2 sizes correct.....the 265 70 16 is .20" taller than the 245 75 16.
With the 245 at 60mph the 265 would be doing 59.7 mph. Now if you ment 265 75 16 that tire is larger and would effect speed, at 60 you would really be doing 56 mph.


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## Morrowmd (Feb 22, 2005)

It sounds like the tires you have on now are bigger- 265/70R16 should be taller and wider than 245/75R16. I doubt that it will make much of a difference in towing either way (maybe slightly with speedometer). My tire guru says you don't want to get a tire to tall and narrow for towing. They have more of a tendency to promote sway.


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## Ghosty (Jan 17, 2005)

I agree with DernMooseAK -- the easiest way to check is to borrow a portable handheld GPS (although I think that everyone should have one who RVs) and test it that way ...

The GPS is extremely acurate when checking speeds and will tell you down to the 1/10 what your true speed is....


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## GlenninTexas (Aug 11, 2004)

It's important to know what came originally on your truck, Is the spare original equipment? If so, check that. The door sticker may or may not reflect the true tire size, mine doesn't.
Then use tha tire size calculator at the following url to compare different sizes;

action=submit" target="_blank">http://www.1010tires.com/TireSizeCalculato...p?action=submit</a>

Increasing tire height has the effect of raising your final drive ratio (lower number ratio). The site above recommends staying within 3% of original size, unless you also intend to change out rearend gears to compensate. You can also re-program your chip using a plug in devise such as Hypertech programmer, if you want to purchase it or know someone who has one. You may also find a dealer that will reprogram the new tire size for you (for a fee).

Regards, Glenn


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## Fire44 (Mar 6, 2005)

The big difference between the two tires you are talking about is the type of tire.

The factory tire was a LT not a P tire. The LT tire is a Light Truck tire and has a higher load rating. The P tire is a Passenger tire and would have a lighter tire rating.

The P265 is orginal equipment on 1500 Suburbans with the LT245's are orginal equipment on 2500 Suburbans.

The difference is sizes of these two tires is very small...but the LT tires will be a better option for towing. With the stiffer side walls the LT tire will give you less sway under a full load.

I have a 2000 1500 Suburban and run the P265 tires now (they came with the truck) but my next set will be a LT tire....I will try and stay around the 265 size if possible.

Gary


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## Reverie (Aug 9, 2004)

No matter what kind of tire you select your safest bet is to always get the size tire the manufacturer called for. It is more that speedometer accuracy, it impacts the entire geometry of your suspension and steering. I know people like to look cool with big, fat tires but if you don't adjust the suspension and alignment to compensate for the change, you will at the least suffer premature tirewear. At the worst you will experience catastrophic tire failure, very bad if you are towing and/or it is a front tire. This isn't just anecdotal, these are specific determinations made by the American Society of Automotive Engineers. I haven't even mentioned brake performance and specifically anti-lock brake performance.

If you plan to tow using your vehicle (and who among us doesn't?) the stiffer sidewalls a tire has, the truer the driving line the vehicle will take. Additional belts or thicker sidewalls reduce sway, shimmy, wheel-hop, and increases control. The down side is that thicker sidewalls increase ride harshness.

Reverie


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## hatcityhosehauler (Feb 13, 2004)

I agree with Fire44. You are comparing two different construction types of tires. It's like comparing apples to oranges. The LT's will be better for towing, due to the stiffer side walls. They will also give you a stiffer ride. I would have to check with tire guy, but I am pretty sure that a P265 and a LT245 are almost the same diameter, and should not require much in the way of re-programming.

Tim


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## camping479 (Aug 27, 2003)

I made the switch on our yukon. An LT245/75/R16 is almost exactly the same diameter as the P265/70/R16. When I checked at tirerack.com, the original equipment for the yukon is the 245's with the 265's as an option.

At first my wife complained about them knocking the teeth out of her head because the ride was so stiff, but once she felt the difference towing, she hasn't complained since.

Mike


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## z-family (Oct 2, 2004)




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