I've never gone to the wider wheel yet for 265's on 2 different Chevy trucks and over 200,000 miles of heavy RV hauling/pulling. My 265's are on the original OEM HD Chrome on Steel rims. Always has handled great and tread wears evenly. Going to the 8" wide wheels should even make it handle better but will show more tire wear over time on the outside tread edge from lowering the psi and also cornering with the wider tire. Lower the psi on wider wheels tends to create a concave left to right tread surface putting more pressure on the tread outside edges directly below the stiff sidewalls. Either wheel width will work fine with the 265's but I prefer even very long wearing tread with 80 psi. A personal choice.