If you go to the 17.5 you will have to most likely replace your hubs. Those wheels use a larger stud. You may be able to have the larger stud pressed your hubs, but i think it is a significantly larger stud. On that axle setup, you are going to just have problems with tires. Sharp turning manuevers what will cause tire problems, but they may not manifest their weakened state until going down the road. The 14 ply trailer tires are a great option on a 16" rim. You need to check your clearance though, becausethey are slightly taller, 235/85/16, whereas the 10 ply trailer tire just an 80 series. I can also tell you from experience that you don't want mix them. Not a rating issue, but the height difference has caused an issue with my equalizers and shackles. I had a load of 2 buildings on my trailer a couple of weeks ago and lost a 10 ply tire on my front axle. The 14s are on the axle. I was loaded pretty heavy and the only sign i had that i had last a tire was some excessive sway on a bumpy road. I stopped at a tire shop and the 14 ply on the back was not the last bit pinched or showing any sign of overloading.
04 3500 LB7 C&C
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