18.4-30 Tractor Tires

Buying 18.4-30 tractor tires

18.4-30 is a rear tire for larger utility and front-wheel-assist tractors. It is about 18.4 inches (467 mm) wide on a 30-inch wheel, the same width as the popular 18.4-38 but on a smaller rim, which makes it shorter overall. It is common on tractors that pull, haul and run a front loader, and it is also made in R-4 industrial tread for loader and yard work.

For radial, the matching sizes are 18.4R30 and 460/85R30. A radial gives more traction and a smoother ride on tractors with a lot of field or road hours; bias costs less and suits loader work.

Easy to confuse

• 18.4-30, 18.4-34 and 18.4-38 share the same width but fit different wheels. Always read the rim size, the last number on the sidewall.

What to check

• Tread: R-1 for field work, R-4 for loader work on hard ground.
• Ply rating: match or exceed your current tires, especially with a loader.
• Front-wheel-assist ratio: changing the rear size or construction can upset the front-to-rear ratio. Check it against your fronts.
• Used tires: ask for the tread depth as a percent, the date code and photos of both sidewalls.

Send the quantity, tread and delivery location for a quote.

What else is 18.4-30 called?

You will see 18.4-30, 18.4×30, 18.4/30 or 18.4 30: a bias-ply tire 18.4 in (467 mm) wide for a 30 in (762 mm) rim. The radial version is 18.4R30, and the metric radial match is 460/85R30.

How does 18.4-30 compare with other sizes?

Nominal figures use the standard size formula with an 85% aspect ratio, so real tires vary. Owners on tractor forums say 18.4-30s are cheaper and more common than the larger rims and suit tractors of roughly 70 hp; on a 100+ hp four-wheel-drive tractor they suggest 34 in or 38 in tires and more weight to avoid wheelspin. That is owner opinion, not a rule, so follow your tractor maker’s tire list. Another owner reports wear of 5 to 10% in about 400 hours on 18.4R30 radials. Your hours and ground will differ.

What do 18.4-30 tires cost on our site?

We list 12 models in 18.4-30. 9 have a listed price, from $475 (Goodyear Dyna Torque II) to $1,197 (CEAT Farmax R1) per tire, with a median of $821. Prices are per tire in US dollars and change with stock and season.

How tall is the 18.4-30 tire?

The nominal overall diameter is about 61.3 in (1,557 mm), which gives a rolling circumference near 193 in (4,890 mm). That figure is an estimate that assumes an 85% aspect ratio, the usual rule for old inch sizes. Real tires vary by make and load, so treat it as a guide and use the tire diameter calculator or the lead-lag calculator before you change size on a front-wheel-assist tractor.

Is 18.4-30 a radial or a bias tire?

It is a bias-ply size. The dash in the size marks bias construction, which costs less and has stiffer sidewalls. See the radial vs bias guide.