Specs on trailer tires

[Frank O]

Recently when I got the two-axle Loadmaster trailer for my 21' center console out of storage, one of the tires blew on the road (thankfully before we picked up the boat). A tire company sent a truck out and put an ST175/80R13 tire on for me.

I then took the trailer to the outboard shop for them to look it over (service the brakes, bearings, etc) before picking up the boat. They said the rest of the tires looked dicey, and recommended replacing the other three. They put on ST175/80D13 tires.

The shop told me that the three tires they put on were more optimized for trailering than the one tire that I got on-the-road, but since I only use the trailer once a year for a relatively brief trip, they didn't think it would be important to have the fourth tire exactly match the other three.

I don't know much about tires, but it would seem to me that the ST designation means that all of these are trailer tires. What's the difference between the 80R13 and 80D13? Do you all agree that the difference isn't a big issue if I don't use my trailer much?

 

[shuswap119]

Re: Specs on trailer tires

Hi Frank O,
The difference is that the ST175/80R13 is a radial ply constructed tire and the ST175/80D13 is a bias ply constuction. You should probably get another bias ply tire to match the other three now and keep the radial tire as a spare.

Regards,

 

[Frank O]

Re: Specs on trailer tires

Thanks, that's kind of what I gathered from what searching I've done so far.

What is the performance difference of bias ply vs. radial ply tires? What could be a potential downside of using one radial-ply tire with three bias-ply ones?

 

[Jeff-in-PA]

Re: Specs on trailer tires

Thanks, that's kind of what I gathered from what searching I've done so far.

What is the performance difference of bias ply vs. radial ply tires? What could be a potential downside of using one radial-ply tire with three bias-ply ones?

They will roll differently and handle differently. They will not well together "as a team" since three bias ply will try to act one way and the radial will be trying something else.

I worked at a tire place during high school, I got a great deal on bias ply snow tires and my car went from handling pretty good to almost uncontrolable due to mixed tire construction.

I would NOT run mixed tires myself.

Jeff

 

[Gary H NC]

Re: Specs on trailer tires

I found the bias ply seem to ride and wear just fine.
Short trips at non-highway speeds and you will probably get by ok with the one radial.
Myself,I would buy one more bias ply and use the radial as a spare.

What brand are the bias ply? You may want to check at Northern Tool if they have them in your area.

Same size on my dual axle trailer and i bought all 4 for under 200 bucks.
That had a good sale going on...

 

[Frank O]

Re: Specs on trailer tires

Thanks, sounds like good advice. The bias-ply tires are Denman Express ST175/80D13. For a fourth bias-ply tire I'm kind of inclined to go through a local tire shop, because I'd like to get the new tire put onto the old wheel and balanced. Then buy a new wheel for the radial that I'd be using as a spare. (As it stands right now, I have no spare.) Just on the theory of keeping everything as matched-up as possible.

Although my use of the trailer every year is brief, it's not non-highway -- basically it's a single annual 26-mile round-trip by freeway. I noticed when towing the boat after the recent new tires were put on that the side with the radial-ply tire appeared to be vibrating noticeably. The boat shop guys said this could be because the radial-ply tire had been installed at roadside, and hadn't been balanced. But I believe they said they then had the tire balanced for me, and it still appeared to be vibrating after that. So, getting another bias-ply tire sounds like a reasonable idea to me.

 

[Gary H NC]

Re: Specs on trailer tires

So many places do not balance trailer tires.I get mine balanced and they feel better to me on the freeway and appear to wear better...

Look at it this way,Now you have a spare!

 

[kenmyfam]

Re: Specs on trailer tires

Agree, best to get them balanced.