People should also be warned that a 215/75/17.5 has a loaded radius about 2" less than a 10.00r15. That can be a big deal if you don't have much ground clearance to start with.[/QUOTE]
:iagree That would be because the 215/75R17.5 does not replace the 10.00R15,just like the 9-22.5 does not replace the 10.00-20.The 215 would replace ,off the top of my head,the 8.25R15.It's all relative.Here's a rundown...8.25-20=9-225,9.00-20=10-22.5,10.00-20=11-22.5,11.00-20=12-22.5.So,off the top of my head(keep in mind I've been away from the tire biz for a few years now)215/75R17.5 would =8.25R15,235=9.00,245=10.00-something to that effect.So you can't compare an orange to a grapefruit:nono.Here's a link(
http://www.ccjdigital.com/continental-touts-low-platform-trailer-tire/) to prove that you can get a Load range J(18 ply rating) 245/75R17.5(google search).Not that I'd recommend a Continental tire,because I wouldn't.Bridgestone or Michelin are my recommendations,followed by BFG(made by Michelin),but that's another discussion.Just know what you are comparing before you go and get too excited,and look a little harder before you denounce it's existence.Remember that it's the ply rating,not size,that ultimately determines load carrying capacity.Smaller size with higher ply rating could have higher load carrying capacity than larger size with lower ply rating.And yes,a 2" difference in radius is a big deal,with more than just ground clearance.