(2) 4 Ply Grassmaster Tires 18x8.50-10 K2581-18140 5075-2

What It Is

This is a set of two (2) 4-ply Grassmaster tires in size 18x8.50-10, designed for zero-turn mowers, riding mowers, and garden tractors that use a 10-inch rim. The 4-ply rating and deep, turf-friendly tread make them ideal for residential mowing on lawns, hillsides, and uneven terrain without damaging grass.

Fitment & Compatibility

Before buying, confirm three things:

• Tire size: Must be 18x8.50-10 (18″ outer diameter, 8.50″ width, 10″ rim). Measure your current tire’s sidewall if unsure.
• Rim width: These fit 7″ to 8.5″ wide rims. Check your rim’s stamped width.
• Load capacity: 4-ply rating supports up to ~590 lbs per tire at 22 psi. Ensure your mower’s weight (especially with a full deck) doesn’t exceed this.
• OEM cross-reference: Common replacements for Cub Cadet, John Deere, Husqvarna, and MTD models using part numbers K2581-18140 or 5075-2. Not a direct OEM fit for all—verify your mower’s original tire part number.
• Deck clearance: Measure the gap between your current tire and the mower deck. The 18″ diameter is standard, but a 0.5″ variance can cause rubbing on tight zero-turn frames.

Key Things to Know

• Quality: 4-ply nylon construction is more puncture-resistant than 2-ply, but these are not for heavy commercial use or rocky terrain.
• Installation: DIY-friendly with basic tools (tire irons, valve core tool). No special adapters needed. Balance is not critical for mower speeds.
• Common gotcha: Tires ship over-inflated (~30 psi). Recommended pressure is 18-22 psi for turf protection and ride comfort. Over-inflation reduces traction and increases lawn damage.
• Tread depth: ~0.5″ deep chevron pattern provides good grip on slopes but may leave slight marks on soft lawns if turning sharply.

Should You Buy It

If you need a reliable, budget-friendly replacement for a residential zero-turn or riding mower, this set delivers solid traction and durability without the premium price of OEM tires. Avoid if you mow rocky or construction-grade lots—the 4-ply rating won’t withstand heavy abuse. For standard lawn care on grass, hills, and dirt, it’s a smart buy.