Husqvarna Weldment.spindle.rh.15.nztr Replaces 436874 Part # 583512901

What It Is

This is the right-side spindle weldment for Husqvarna and compatible zero-turn mowers, specifically designed for 15-inch NZTR deck models. It houses the blade pulley and bearing assembly, transferring engine power to spin the cutting blade.

Fitment & Compatibility

• OEM part number: Replaces Husqvarna 436874; part # 583512901 is the OEM version. Aftermarket equivalents exist but may vary in bearing quality.
• Deck size: Fits 15-inch NZTR (New Zealand Turf) decks only. Not for 12-inch or 18-inch decks.
• Models: Compatible with Husqvarna Z242F, Z254F, Z4219, Z4219B, Z4219T, and select Poulan Pro and Craftsman zero-turn mowers. Check your deck’s model number or existing spindle for confirmation.
• Measurement check: Measure center-to-center bolt hole spacing (typically 2.75 inches) and spindle shaft diameter (0.75 inch) to verify fit. If your existing spindle has a different bolt pattern or shaft size, this won’t work.
• Side note: This is the right-hand spindle. The left-hand spindle (part # 583512902) is a separate purchase.

Key Things to Know

• Quality: OEM Husqvarna construction is robust; bearings are sealed and pre-greased. Aftermarket options may use cheaper bearings that fail faster.
• Installation difficulty: Moderate. Requires removing the blade, pulley, and retaining hardware. You’ll need a socket set, a torque wrench, and possibly a puller for the pulley. Allow 30–60 minutes.
• Common gotcha: The spindle mounting bolts can seize. Use penetrating oil and heat if needed. Replace bolts if they strip.
• Blade alignment: After installation, check blade tip height and deck leveling. A misaligned spindle can cause uneven cut.

Should You Buy It

If you own a Husqvarna zero-turn with a 15-inch NZTR deck and need a direct OEM replacement for the right-side spindle, this is the right choice. It’s priced competitively, rated highly for durability, and avoids the fitment risks of aftermarket spindles. Skip it if you need a left-side spindle or a different deck size.