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Tiremaxx Service Centers
145R12 trailer tires at Tiremaxx in St. Joseph, MN

Specialty Trailer Tires

145R12 Trailer Tires

What 145R12 means, what else fits the same wheel, and how to get the right load range, from the Tiremaxx tire crew in St. Joseph, MN.

Wheel
12"
Construction
Radial
Section width
5.7"
Overall dia.
—

What 145R12 means

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

  • 145Section width145 mm (about 5.7 in) across the widest part of the tire.
  • RConstructionRadial. The body plies run across the tire. Radials generally run cooler at highway speed and wear more evenly.
  • 12Wheel diameterFits a 12-inch wheel. This is the number that has to match your rim exactly.

Size is only half the answer

Two 145R12 tires can be rated for very different weights. Load range (B, C, D, E and up) sets how much each tire can carry at its rated pressure, and on a trailer that number matters as much as the size does. Your trailer's certification label, usually on the front left of the frame, lists the size and load range it was built for. Bring us that label, your paperwork or the old tire and we'll match the load range to what you actually tow.

Commonly used on: compact and light-duty trailers.

Other sizes on a 12" 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.

145R12 questions, answered

145: 145 mm (about 5.7 in) across the widest part of the tire. R: Radial. The body plies run across the tire. Radials generally run cooler at highway speed and wear more evenly. 12: Fits a 12-inch wheel. This is the number that has to match your rim exactly.

Specialty Trailer (ST) tires are built with stiffer sidewalls for towing loads and are rated differently than passenger tires, so they aren't interchangeable just because the numbers look similar. Your trailer's certification label lists the size and load range it was built for. Matching it is what keeps the load capacity you're supposed to have. Bring us the label or the old tire and we'll match it.

We carry 4.80-12, 5.30-12 in the same 12-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.

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.

← All specialty trailer tire sizes

Pull up to the counter

Need 145R12 on the trailer?

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

Schedule ServiceCall (320) 363-7246