Trailer Tire Size Problem

[Rizzo]

Bought a new spare tire for the trailer. Current tires are 5.30 - 12 so thats exactly what I bought. Got home and the new tire seems to be at least an inch bigger diameter than the existing tires. I measured and the new one is about 1 inch bigger diameter. Could pressure differences in the tires make that much of a size difference (ie the new tire may be at 80 psi and the existing tires only at 50?). I tried to measure the pressure but my crappy tool only goes to 50 psi and they both reached that. Is it possible that different manufacturers have a different idea of what 5.30 - 12 is? For example, my wife is a size 6 at store A, but a size 8 at store B (take a guess where she ends up buying :rolleyes: )

[Bly]

Evening Rizzo

 

This might seem like a silly question, but is the original tire still on the trailer with the boat on it? When I purchased our spare tire and rim, it also looked to be about an inch bigger, checked the size, was correct, measured the rims, they were the same but being me and not wanting to take any chances, jacked up the trailer. Tires are the same size.

[Rizzo]

thanks Bly, I had thought about that (could the load on the tire be causing the difference) but for some reason I had envisioned taking the tire right off to compare (too much work for a lazy fart). But just jacking the trailer up will accomplish the same thing (getting the load off the tire). I will give that a try when I get home. Thanks for the input

[bassjnkie]

50 psi? My tire is 30psi max. My car tire is 30psi.

 

I think the tire is ove inflated.

 

But anyways back to the post. I bought a spare tire last year and yes it looked bigger, as long as the numbers match your golden.

 

Hope this helps,

Daniel

[Fisherman]

50 psi? My tire is 30psi max. My car tire is 30psi.

 

I think the tire is ove inflated.

 

But anyways back to the post. I bought a spare tire last year and yes it looked bigger, as long as the numbers match your golden.

 

Hope this helps,

Daniel

No, it doesn't, load range B tires, 50 psi, load range C tire 80 psi, inscribed on the sidewall, these are not car tires.

[bassjnkie]

No, it doesn't, load range B tires, 50 psi, load range C tire 80 psi, inscribed on the sidewall, these are not car tires.

 

Sorry it's my mistake, I was thinking of a different tire. 50psi is correct it's B. Sorry for the confusion. I messed up.

 

Sorry continue with the post.

 

Daniel

[pikehunter]

Could it be the tread depth? New tire has no wear and your existing tires have been worn.

Don't know just a thought at 4AM.

[Wild]

Rizzo the tire size is a standard measurement and Bly is correct. The important question is does this new tire have the same ratings as the others? Load rating? PSI rating?wear rating? tread pattern and construction? The small details can make a big difference when it matters the most.

[Rizzo]

mmmm, wasn't aware of all these other issues, I just saw they were both 5.30-12 and bought it! Guess I'll take a closer look tonight.