245/75/16 E tires to 265/75/16 E tires

Grit dog wrote:
Thanks for all that Benk. Would think someone as knowledgeable as you would know 10" wide rims are too wide for 265 tires.......
To the OP, you'll be fine. More than likely the speedo is calibrated to larger tires anyway. Every work truck I've gotten with the little oe tires on steelies has read fast and going up a couple sizes got the speedo close to actual speed.

Ben ,as some of us were probably boy racers when we were younger. As some type of racer we played around with narrow and wide rims trying to get a particular performance from a tire on dirt or paved tracks. These vehicles had nothing to do with carrying weight.

Now when we move into the trucking world were more concerned with proper tire/wheel match for best load carrying performance and less stress on the tire.
A load carrying tire is happier when the rims width closely matches the tires tread width.
A 265/75-16 or 17 tire may have a tread width up to 8.2" wide. Some of GM OEM 16"-17" truck wheels are only 6.5" wide. Not the best idea for a load carrying tire. I've tried the LT265/75-16 E on 6.5" OEM wheels on a '92 chevy truck with terrible handling and wear issues.
Tire makers show a rim width range for a particular tire. One tire maker shows a 7"-9" wheel width recommendation for a tire with a 9" wide tread. A 7" wide wheel would not be a good idea for a tire with a 9" wide tread whan carrying heavy loads.
Just be aware of tire tread width/wheel width fitment when it comes to tires that carry heavy loads. Yes it matters.