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Tiremaxx Service Centers
400/70R18 construction & OTR tires at Tiremaxx in St. Joseph, MN

Construction & OTR Tires

400/70R18 Construction & OTR Tires

What 400/70R18 means, what else fits the same wheel, and how to get the right load range, from the Tiremaxx tire crew in St. Joseph, MN.

400/70R18 tires we carry

1 option 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
Radial
Section width
15.7"
Overall dia.
40"

What 400/70R18 means

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

  • 400Section width400 mm (about 15.7 in) across the widest part of the tire.
  • 70Aspect ratioThe sidewall height is 70% of the section width. A lower number means a shorter sidewall.
  • RConstructionRadial. The body plies run across the tire. Radials generally run cooler at highway speed and wear more evenly.
  • 18Wheel diameterFits a 18-inch wheel. This is the number that has to match your rim exactly.

Also written as

The same tire is cross-referenced as 405/70R18. If that's what's on your old tire or your paperwork, you're in the right place.

Size is only half the answer

Two 400/70R18 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 400/70R18's 40" height, on various wheel sizes.

400/70R18 questions, answered

400: 400 mm (about 15.7 in) across the widest part of the tire. 70: The sidewall height is 70% of the section width. A lower number means a shorter sidewall. R: Radial. The body plies run across the tire. Radials generally run cooler at highway speed and wear more evenly. 18: Fits a 18-inch wheel. This is the number that has to match your rim exactly. Altogether that works out to roughly 40 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 12.5/80-18, 365/70R18 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.

Yes. 400/70R18 and 405/70R18 are cross-references for the same tire, written in different notation systems. Trailer and equipment tires are often listed both ways, so don't worry if your paperwork and your sidewall don't look identical.

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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Pull up to the counter

Need 400/70R18 for the job site?

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

Schedule ServiceCall (320) 363-7246