Originally Posted by BobChill
I want to replace the tires with Michelin Defender LTX M/S tires but the only 20" size that has E load rating is 265/60/20 so it has a smaller diameter. Are there any issues putting 265s on the truck? I assume the 275s aren't available with E load rating because of the taller sidewalls?
If you insist on Michelin Defender LTX MS, then Michelin does not make that size in an LT tire with load range E. Michelin does make that size in P-series which is close to equivalent to load range C of an LT tire.
If you want that tire in load range E, then you must either move up to size LT275/65R20E or down to size 265/60R20. Either one should work just fine on your truck. If your truck is a 4x4, then be sure to change all 5 tires to the same size.
How will size LT265/60R20E affect your truck? The difference can be estimated by the percentage change in the tire revolutions per mile (revs/mile).
New tires = LT265/60R20 = 640 revs/mile
Stock tires = P275/60R20 = 630 revs/mile
640 minus 630 = 10, divided by 630 = 1.6%.
So your effective axle ratio will be changed by 1.6%, and your speedo (compared to now) will be off by 1.6%. That's probably not enough difference to be noticeable. If you have 3.55 axle, it will "feel like" a 3.57.
Grumpy ole man with over 60 years towing experience. Now my heaviest trailer is a 7,000-pound enclosed cargo trailer, RV is a 5,600 pound Skyline Nomad Joey 196-S, and my tow vehicle is a 2019 F-150 Lariat 3.5L EcoBoost SuperCab with Max Tow (1,904 pounds payload capacity).