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Upgrading from 245s to 265s.... pros and cons of doing this to my truck

I like to research my options before committing to them and then finding out I made a mistake! So I have been reading post after post about many others that have changed tire size on their vehicles. I am not talking about a large difference, but according to the posts that I have read, many people have stated what they think are the pros and cons to changing tire size.

In particular, I am looking for pros and cons to upgrading to a LT265 75 R16 from the LT245 75 R16 on a Chevy Silverado Ext. Cab K1500 4x4. The tire I want to upgrade to is a Firestone Destination AT. I am currently running Firestone Steeltex.

THE PROS are: 1) Better looking tire for a 2004 K1500 Silverado 2) a little more ground clearance

THE CONS are: 1) Worse gas mileage (Not sure if it adds up to a lot) 2) More surface contact and less “traction” in the winter time 3) Price

I was wondering if anyone out their has had any experience with this and would the pros OUTWAY the cons? Thanks for any advice!

The LT265-75R16 is an optional size for your truck (according to Tire Rack), so fitment should not be a problem. I replaced the Uniroyals on my 2000 Blazer with Destination LE’s a few years back. The LE’s tend to wander a bit more than the Uniroyals, but the rain, mud, and snow traction are magnitudes better than the Uniroyals. Even with 30k on the tires, they still hold the road well.

Based on my experience with the LE’s, the Destination AT’s are on the short list to replace them on the Blazer. I want a more aggressive tire for light off-roading.

Ed B.

Why do you think you are going to gain ground clearance? The only thing I see on the plus side is that you like the “look” better.

The different tire size will be 20mm wider (about 7/8") and about 7mm taller (less than 5/16"). Your additional ground clearance will be half the tire’s extra 7mm of height, plus the difference in tread depth. You will have no appreciable difference in ground clearance. Going with this size will not hurt anything, but you will not really gain anything either. The only real reason to go with this size would be if the tires you want are not offered in your original size. The extra width probably will look nice, though, but the extra rolling resistance may cost you a little in gas mileage.

Edb1961,

I really liked the Destination LEs that I put on my wife’s explorer a few years back. They were much better than the OEMs in rain and snow. Looking forward to the more aggressive ATs. I saw that optional tire size was the 265s but didn’t know if I needed to adjust anything other than the speedo if I put them on in place of the 245s. Not to worried about the speedo.

Oldtimer 11,

I think the 265s will have a larger diameter of around an inch from reading other posts and using a tire size website to calculate the actual diameter - I know their is a precise actual size but to lazy to look it up at midnight- but in all honesty I used the plural of PRO in my post and thought I better come up with at least two PROs :slight_smile:

If you do a lot of driving in the snow then the 245 would be the better choice…

But I really don’t see a problem with putting those tires on.

Since this tire size is optional for your truck you will have no problems. Your fuel economy may suffer a little due to the weight of the tires and better gripping power. You may find that your truck stops a little faster than normal. Remember…the tires are what actually stops your truck not the brakes. The brakes just stop your wheels.

If the tires compress equally, you will get an extra 0.6 inches of ground clearance. The circumference will increase a bit less than 4%. That’s not a lot of change in speed.

265 70 R16 would look even better and be almost exactly the same rolling radius.
As you know, the first number is the width of the cross section. the closer the tread is to the cross section area of the tire is the wider the tread is. A lower profile put the tread closer to the cross sectional area.

I did this on my 97 chevy. It now shows about 4 mph slow on the speeddo. This has been checked by radar and GPS. My gas MPG is about the same 15-16 around town 19-20 Hwy. The tire I went with is a GoodYear Wrangler LT. The traction is grate. I have no problem going thru 1-2 foot of snow. I cut firewood in the winter so I dive the two tracks alot in the winter. I was in Detroit last winter when they got 8 inch’s of snow with ice under it had no problems in 2 wheel Dr but I put it 4 wheel Dr for safety. I paid just under $600.00 for them.

I like the idea that the truck will stop faster… that is the first time someone has mentioned the stopping power of larger tires. I am comfortable with driving in the snow so I think that having the 265s will not be a big deal for me. I am going to check out the prices on some 265 70 R16s as well. I figured that the size increase was not so great that my gas mileage would suffer. Also glad to hear that gas mileage does not tank with this upgrade. Thanks again for all the info.

It’s a mistake to assume that a larger tire will stop the car faster. A tire’s “footprint” is a function of its load in pounds and its air pressure. On vehicles with narrow tires for the car’s size, the tire may stop the vehicle faster by better reacting to the added load of stopping (the weight shifting to the front) and keeping its tread flatter, but on a vehicle whose tires are sufficient for its size and whose brakes are marginal the added rotating mass may more than offset the better traction under dynamic loads.

Try this experiment. Spin a road bike’s wheel as fast as you can by hand and try to stop it by squeezing the sides of the rim. Then do the same with a mountain bike. You’ll find that the difference in rotating mass makes a big difference. The mountain bike wheel will be clearly harder to stop. The same principle applies with cars and brakes.

Thanks for the info… I will go spin the tires on my Specialized Rockhopper and compare to the old road bike in the garage.

Your Rockhopper has aluminum rims. Just be sure when you compare that the old road bike also has aluminum rims. The old dime store bikes commonly had steel rims, and that’ll mess up the comparison.

You can check with a refridgerator magnet.

The larger tires will be 30mm larger in diameter, not 7mm. With the compression of the tire, 0.6" increase in ride height sounds about right.

The differences in traction are going to be more due to the tread and rubber compound than the tire size. If you were comparing the same model tires, then the traction differences would be due to the size.

If the circumference is 4% greater (3.9%) and you measure a 4% decrease in measured gas mileage, you are actually breaking even. BTW, there is about a 2% difference between new tires and worn tires of the same size.