Paying $35–45 per lawn mower blade at the dealership gets old fast, especially when you find out the same cut quality is possible with $15–25 aftermarket blades that bolt on exactly the same. Many homeowners stick with OEM blades because they are unsure how to cross-reference part numbers or verify compatibility. Others are worried that a wrong blade might vibrate, scalp the lawn, or damage spindles.

The good news is that a structured lawn mower blade cross reference makes it simple to move from OEM to aftermarket without guesswork. By matching five key specifications—blade length, center hole style, thickness, lift profile, and mounting pattern—you can safely interchange blades across major brands like Craftsman, Cub Cadet, John Deere, Husqvarna, Troy-Bilt, and MTD while cutting your costs by 30–50% per set.

Aftermarket leaders such as Oregon, Stens, Rotary, MaxPower, and Arnold publish detailed catalogs and online fit guides that map OEM part numbers directly to their equivalents, including Gator mulching and high-lift options. When combined with a basic understanding of mower deck sizes, spindle patterns, and lift requirements, a good cross-reference table becomes as valuable as any dealer parts counter. If you are also maintaining rear or finish mowers, pairing blade selection with the right deck hardware and wheels further extends equipment life.

Understanding Mower Blade Specifications and Compatibility

Blade length is measured tip-to-tip in a straight line and must match the deck size and overlap requirements, such as 21″ blades on a typical 42″ twin-blade deck. Center hole diameter and shape—5/8″ or 3/4″ round, 5-point star, or 6-point star—must match the spindle shaft or adapter exactly to avoid slippage. Blade thickness, commonly around 0.187″–0.204″, influences strength and balance; mixing thicknesses on the same deck can cause vibration.

Offset and lift describe how much the trailing “sail” section of the blade bends upward to create airflow. High-lift blades throw clippings farther and bag well but need more engine power, while low- or medium-lift designs reduce dust on sandy lawns. Finally, the mounting hole pattern, including any secondary holes for bolts or anti-scalp features, must match exactly because even a small pattern mismatch can prevent installation. For users managing larger finish mowers, matching these specs goes hand in hand with choosing compatible wheels and hardware.

How to Measure Your Existing Mower Blade

Start by removing the spark plug wire and blocking the blade with a scrap of wood before loosening the mounting bolt. Once the blade is off, clean it with a wire brush so rust and grass do not interfere with measurements. Lay it flat on a bench and use a tape or caliper to measure the overall tip-to-tip length in a straight line, not following the curve.

Next, measure the center hole diameter or confirm whether it is a star pattern that keys to the spindle, and note any additional side holes. Check thickness with a caliper if possible and inspect the lift section to determine whether it matches a high-lift, standard, or mulching design. When you service the rest of the deck—such as wheels, belts, and spindles—doing blades at the same time minimizes downtime.

For owners of finish mowers and rear-mounted decks, combining accurate blade measurements with regular spindle bearing maintenance dramatically improves cut consistency. Detailed spindle replacement guides walk through bearing replacement and torque specs so the new blades run smoothly at full RPM. While blades and belts serve different functions, the same attention to specification matching applies when comparing Kevlar versus standard mower belts for long-term durability.

Complete Brand Cross-Reference Tables

These cross-reference lists focus on common 42″, 46″, 48″, and 54″ decks used on lawn tractors and zero-turn mowers. They include both standard and mulching designs so you can choose a blade that matches your cutting style, whether you mulch leaves or side-discharge clippings. For additional context on blade cost versus performance and deck size, comparing finish mower blade options can help set realistic expectations for wear and sharpening intervals. Like blades, our zero-turn wheel guide shows compatible aftermarket wheels.

Craftsman OEM to Aftermarket Cross Reference

Craftsman lawn tractors commonly use 21″ blades on 42″ decks under OEM numbers like 134149, 127843, 138498, 138971, and related AYP part numbers. Many of these interchanges also fit Husqvarna and Poulan riders using the same 5-point star spindle design. Oregon, Stens, and Rotary publish direct-fit replacements with the same length and center-hole pattern, making it straightforward to upgrade to mulching or high-lift designs while keeping compatibility.

Cub Cadet OEM to Aftermarket Cross Reference

Cub Cadet riders and zero-turns often use 21–21-1/8″ blades on 42″ decks with OEM numbers like 742-04126, 742-04308, 759-03822, and 942-0616, plus longer blades on 46″ and 54″ decks such as 742-0677 and 742-04415. Because Cub Cadet belongs to the MTD family, many of these blades interchange directly with Troy-Bilt and other MTD-branded machines.

John Deere OEM to Aftermarket Cross Reference

John Deere 42″ decks typically use 21-3/8″ blades like GX22151 and GY20850, while larger 48″ and 54″ decks use blades under numbers such as AM137328, AM141033, M113517, M143111, and M145516. These blades commonly have a 7-point star center and are well supported in the aftermarket by Oregon, Stens, Rotary, and MaxPower.

Husqvarna OEM to Aftermarket Cross Reference

Husqvarna uses a mix of 21″ blades on 42″ decks (such as 532138971) and 16–16-5/8″ blades on 48″ fabricated or stamped decks with part numbers like 532173920 and 532173921. Some Husqvarna blades interchange directly with Craftsman/AYP models, and many share cross references with John Deere blades when using 7-point star centers.

Troy-Bilt / MTD OEM to Aftermarket Cross Reference

Troy-Bilt and other MTD-branded tractors often share blades with Cub Cadet models, particularly for 42″ and 46″ decks. Common part numbers include 742-04308, 742-04126, 942-0616, 742-04290, 942-0677, and 742-04415, typically in the 21–21-3/16″ range for 42″ decks and around 18″ for 54″ decks.

Aftermarket Manufacturer Quality Comparison

Oregon is widely regarded as a premium manufacturer, supplying standard and Gator mulching blades that match OEM dimensions while often costing 20–40% less than dealer blades. Stens focuses heavily on commercial and dealer channels, with its Silver Streak line targeting professionals who want consistent balance and long life. Rotary emphasizes value, using copperhead branding for many mulching and high-lift designs used on common riding mowers.

MaxPower offers widely sold 3-in-1 and mulching sets, including blades like the MaxPower 3-in-1 for John Deere GX22151/GY20850, commonly found at Tractor Supply and online. Arnold sells a range of budget and mid-range replacements, including Extreme mulching blades compared in independent blade tests. Matching these blades to your mower’s deck, along with regular gearbox leak checks on finish mowers, ensures long service life and consistent cutting across the season.

Where to Buy and Installation Tips

Amazon typically has the widest selection of Oregon, Stens, Rotary, MaxPower, and Arnold blades, along with accessories like blade balancers and torque wrenches for precise installation. Walmart.com, Home Depot, Lowe’s, Tractor Supply Co., and Northern Tool all stock selected part numbers, sometimes favoring specific brands like MaxPower or exclusive private-label blades. When comparing total cost, factor in shipping and consider combining blade purchases with other tractor maintenance tools.

When installing replacement blades, always disconnect the spark plug wire and tip the mower so the air filter and carburetor stay up to prevent fuel leakage. Use a wood block to keep the blade from turning while loosening or tightening the bolt, and mark the deck side of the old blade to avoid confusion about orientation. Many manufacturers recommend torque values around 35–40 ft-lb for typical walk-behind and lawn tractor blades, so a torque wrench pays for itself quickly. Don’t forget proper hardware – see our blade bolt cross-reference guide to find the correct bolts, washers, and torque specs for safe blade installation. Need a new mower Belt?

❓ Frequently Asked Questions

Aftermarket blades from Oregon, Stens, Rotary, MaxPower, and Arnold commonly save 30–50% versus OEM pricing, often trimming $10–65 per purchase depending on deck size and blade count. Oregon and Stens are widely trusted for reliability, while Rotary and MaxPower deliver strong value for typical homeowners mowing weekly. For safe mower blade interchange, always match length, center hole, thickness, lift profile, and mounting pattern, and source blades from reputable retailers like Amazon, Home Depot, and Tractor Supply Co with clear cross-reference data.

For comprehensive mower maintenance guides and parts information covering all outdoor power equipment, explore our complete resource library. Visit Tractor Parts Central homepage