[fcatwo]

Bill

Thanks for not being offended by my attempt at humor. Re your questions: TMO member Senorsedona is the only person I know of who actually replaced his 215s with 225s. He reported good results although I think he traded up soon after. I'm almost sure he had the lift kit.

I spent many hours researching the possibility of switching when I bought new tires a few months ago but finally decided to stay with the 215s -- primarily because we have had no tire problems in 25-30K miles and 5yrs of TM towing. I don't know why we've been so lucky but we do travel lighter than most and avoid hot weather. I don't know if it matters but we also use a 600lb WDH which may be a little easier on the TM tires. I pulled my wheels and took them in to have the new tires mounted and balanced and found that getting the 215s off and on without removing the skirts was borderline even though we have the lift kit. I suspect you'd have to remove the skirts with 225s.

mtnguy

It's not a big deal but I think the 225s are only 0.3 wider than the 215s and not 0.8 (8.8 vs 8.5). They are significantly taller however and the lift kit is probably mandatory for their us. For info: I recall that RMR asked the TM factory at one time about using 225 tires on their 3500lb axles and was told they had not tested that combination and could not recommend it. IMO Bill has thoroughly tested the 215s on the 3500lb axle and found them wanting so it's time for the factory to get with the program. I can't answer the question about any possible offset difference between the 14" and 15" 5X4&1/2 rims. I planned to take one of my 14s to Camping World and compare it to a 15 to make sure they are the same but never reached that point. I should mention the the 15" rims are only about $40.00 each and the 225 tires are only about $10.00 more than 215s -- so it's a $150.00 upgrade at tire change time or a $500.00 upgrade otherwise.

wmtire

Thanks for sharing your professional expertise. I'm sure you have other things to do but don't forget us. We have Bill and a couple of others who know electricity and electronics but you are the first tire professional I recall seeing here. I think we also have an engineer or two and even a metalurgist but they are cautious about their postings.