Forum Discussion

FrankoToo's avatar
FrankoToo
Explorer II
Jan 08, 2020

Trailer Tire Speeding Rating??

Recently purchased the new-to-us TT in my sig. For piece of mind, I plan to replace the tires in the very near future. Current tires are Rainier ST235/80R16 Load Range E. Since this is not a large trailer, I'm not overly concerned about overloading. My question is about speed rating. I've searched and read a few posts here but to be honest, the info went over my head. Most ST tires are limited to 65 mph at 80 psi. Would I get anything more by going to an LT tire in the same size or assuming the rims can handle the extra pressure, moving up to a LR F or G tire? It's not my goal to fly down the road doing 80 but know 70 or so is safely doable in parts of the country where higher speeds are allowed. Trailer gross is 11,200, axles rated at 5200. My rims are the only unknown at this point.

Thanks in advance.
  • OP's TT tongue wt percentage 860/6740= 13%. At GVWR 11,260, 13% is 1,463 so at GVWR, axle wt is 11,260 - 1463 = 9,797 and /4 = 2,450 per tire needed.

    OP's STs now 3,520 per tire at 80PSI, but LT would be more like 2,680 at 80PSI (so wheels can take that same as for ST) but still enough for weight but just enough margin for uneven wts per tire as is common with RV loading.

    Since newer STs are good for higher speeds, all that would happens is OP loses weight margin, no speed advantage.
  • FrankoToo wrote:
    Most ST tires are limited to 65 mph at 80 psi.


    The 65mph speed rating for ST tires is outdated information. I want to say it was 2-3 years ago that ST tires started coming with speed ratings stamped on them.

    Edit to add, it looks like eTrailer has a question/answer on their site about this:
    https://www.etrailer.com/question-152234.html
  • FrankoToo wrote:
    MDKMDK wrote:
    Can't you get new rims that would match the higher rated tires?


    That would be worse case scenario but yes, I could always get new rims. Just don't want to spend the money if I don't have too.


    If the higher rated tires were to cause a catastrophic failure with the current wheels, you could be creating a dangerous combination, and your insurer may have a problem with the user mod that created it. If they notice it, of course.
    Just sayin'.....
  • https://www.cruiserrv.com/2018/travel-trailers/stryker-toy-hauler/st-2313/

    Looks like you have no weight issues with the current set-up, so as you say, no need for LTs just for that.

    Before looking at new wheels, check what PSI you would be using in any LTs to meet the weight. You don't fill them all the way no matter what like you do with STs. So your LT proper PSI could be 65 lbs or less anyway, so current wheels would be ok. Don't forget tongue weight takes some of the weight, which helps.

    Once you have your LTs at PSI for the weight, if you can then go faster, IMO it would not be any faster with bigger stronger LTs than any LTs that fit now. AFAIK.
  • MDKMDK wrote:
    Can't you get new rims that would match the higher rated tires?


    That would be worse case scenario but yes, I could always get new rims. Just don't want to spend the money if I don't have too.
  • Can't you get new rims that would match the higher rated tires?

About Technical Issues

Having RV issues? Connect with others who have been in your shoes.24,194 PostsLatest Activity: Feb 01, 2025