Will Radial 185/80-13 Tires Put More Stress Than Bias Tires on Jayco Jay Feather Trailer

Question:

I just had my tires change on my 17 ft Jayco Jayfeather Sport 2011. I told then I needed to replace them at a tire store and told them the tire is a ST 185/80D13. They ordered them and I had them put on. I just returned from my first trip with the new tires and they felt different pulliing and only need 50 psi instead of the 65 psi that my tires normally do. When looking closer the tires they replaced on my camper are ST185/80R13 not ST185/80D13. Would this change how my camper is pulled. It seems my 80 D 13 could handle the load better and not put so much stress on my car. Does this make a difference. Im pretty upset as I told them I wanted the identical type of tires and they put the R13s on. I feel a little duped. Is there much of a difference and weightload? Would the R13s put more stress on my care than the D13?

asked by: Mary L

Expert Reply:

That's an interesting scenario because we normally recommend going with the radial-type tires or bias-type for highway usage. The radial (R13) have more flex in the sidewall which should give it better performance on the highway and help keep the heat down. If I were you I'd double check the psi rating on the sidewall. We have the Kenda Karrier ST185/80R13 Radial Trailer Tire # AM10208 which is rated for 65 psi so it could be that the air isn't inflated to what the sidewall calls for - this would definitely affect performance and how much your tow vehicle is having to work.

Bias tires (D13) are sufficient for highway use but they have a stiffer sidewall so they are becoming less popular for highway use and used more for off-road and agricultural trailers since they do a better job at withstanding rougher terrain.

I really think the psi rating on the tire isn't being followed as I have yet to hear about someone noticing a difference in performance when switching from bias to radial - at least a negative performance.

expert reply by: Jon G