Tire aspect ratio

comments embedded in red

agesilaus wrote:
I got a new to us 2018 Ram 6.7L 2500 and it is mostly great. But it came with Sailun mostly worn out tires 275/R70 18 tires. Escapees right now have a fantastic discount on Michelin 275/R70 18 tires at $105 off each tire.

My understanding is that R75 means 70% or the height of the tire and R65 means 65%.

I assume that not a problem. The ones I'm looking at are

Assumptions can get expensive

Michelin P275/65R18 114T LTX AT2 DT

the "P" indicates a 'passenger car' tire and has to be de-rated min of 9% when used on a pickup/SUV

Some countries will fine the tire dealer and tow a vehicle away if it has the wrong class of tires on it

Your TV should have LT class tires of the size your manual says and if you change the sizing...you are re-engineering your suspension

Many will say just do it or go for it, but they have no skin in your game. If it doesn't fit...expensive to replace/buy a new set...if it under rated...potentially dangerous situation at the limits

LTX AT2 at $245 discounted

the "LT" indicates a 'light truck' tire and does NOT need to be de-rated when used on a pickup/SUV

These are images representing how aspect ratio affects the tire/wheel combo. Lower aspect ratio of the exact same section width & wheel dia will change the overall tire dia & width