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Tiremaxx Service Centers
12.5/80-18 construction & OTR tires at Tiremaxx in St. Joseph, MN

Construction & OTR Tires

12.5/80-18 Construction & OTR Tires

What 12.5/80-18 means, what else fits the same wheel, and how to get the right load range, from the Tiremaxx tire crew in St. Joseph, MN.

12.5/80-18 tires we carry

3 options in this size. Call (320) 363-7246 for price and availability, or request the one you want.

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Our lineup refreshes from the warehouse system every 30 minutes. Call to confirm availability before you drive out.

Wheel
18"
Construction
Bias-ply
Section width
12.5"
Overall dia.
38"

What 12.5/80-18 means

Every number on the sidewall is telling you something. Here's this one, decoded:

  • 12.5Section widthAbout 12.5 inches across the widest part of the tire.
  • 80Aspect ratioThe sidewall height is 80% of the section width. A lower number means a shorter sidewall.
  • –ConstructionBias-ply. The plies run diagonally, which gives a stiff, tough sidewall.
  • 18Wheel diameterFits a 18-inch wheel. This is the number that has to match your rim exactly.

Equivalent sizes

The equivalent of 12.5/80-18 in the other construction is 340/80R18. Bias and radial versions stand close to the same height but are built differently, so tell us which one you run.

Size is only half the answer

Two 12.5/80-18 tires can be built for very different work. Ply or star rating sets how much load each tire carries, and the tread code (R-4 industrial, L-2 traction, L-3 rock and so on) sets the ground it's built for. Tell us the machine and the work it does, and we'll match the tire to the job, not just the numbers.

Other sizes on an 18" wheel

These share your rim diameter. Whether one of them will actually work depends on rim width, load range and fender clearance. Ask us before you switch.

Similar overall diameter

Within about 3% of 12.5/80-18's 38" height, on various wheel sizes.

12.5/80-18 questions, answered

12.5: About 12.5 inches across the widest part of the tire. 80: The sidewall height is 80% of the section width. A lower number means a shorter sidewall. –: Bias-ply. The plies run diagonally, which gives a stiff, tough sidewall. 18: Fits a 18-inch wheel. This is the number that has to match your rim exactly. Altogether that works out to roughly 38 inches of overall diameter.

The size has to match, but so do the ply or star rating and the tread. A machine working pavement and concrete wants a different tread than one in mud or a gravel pit, even in the same size. Tell us the machine and what it works on and we'll steer you to the right tire.

We carry 365/70R18, 400/70R18 in the same 18-inch wheel diameter. Sharing a rim diameter doesn't guarantee a swap will work, though. Rim width, load range and clearance all have to line up. Call (320) 363-7246 and we'll tell you straight whether a change makes sense.

They're equivalent sizes. 12.5/80-18 and 340/80R18 fit the same wheel diameter and stand close to the same height, but bias and radial tires are built differently, so they shouldn't be mixed on one axle without checking. Tell us which one you run and we'll match it.

Stock moves, so the honest answer is to check. Send us the size through the availability request on this page or call (320) 363-7246. We'll tell you what we have on the shelf, what load ranges are available and how fast we can get anything we'd need to order.

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Need 12.5/80-18 for the job site?

Tell us the size and load range and we'll prepare a no-pressure quote.

Schedule ServiceCall (320) 363-7246