Replacement 7" 10 Blade Transmission Fan 53821 Fits Hydro Gear，Gravely，Ariens，Scag Liberty Z，Bad Boy MZ，Hustler Raptor XDX Zero-Turn Mower

What It Is

This is a replacement transmission cooling fan (7-inch diameter, 10 blades) designed for zero-turn mowers. It bolts onto the Hydro-Gear transaxle to keep the hydraulic fluid cool during heavy mowing.

Fitment & Compatibility

• Primary fit: Hydro-Gear transaxles (EZT, ZT-2800, ZT-3100, ZT-3400 series) on Gravely, Ariens, Scag Liberty Z, Bad Boy MZ, and Hustler Raptor XDX.
• Check before buying: Remove your old fan first. Verify the center hole diameter (typically 1/2” or 5/8”) and blade count—this fan has 10 blades, so don’t swap in a 6- or 8-blade fan.
• OEM cross-reference: Replaces OEM part 53821 (Hydro-Gear). Not a direct fit for all zero-turn brands—measure fan-to-frame clearance; some decks may require a thinner or offset fan.
• Physical dimensions: 7” diameter, 10-blade design. If your existing fan is 6” or 8”, this won’t fit without changing the mounting bracket.

Key Things to Know

• Quality concerns: 3.7/5 stars and 11 reviews suggest mediocre reliability. Several users report blade cracking after 1-2 seasons on heavy-use machines.
• Installation difficulty: Easy—remove the old fan (usually one bolt or snap ring), slide the new one on, and tighten. No special tools needed.
• Common gotcha: The fan can rub against the mower frame if the transaxle is shifted. Check clearance by hand-spinning the fan after install.
• Noise: Some users note a slight wobble at high speed; ensure the shaft is clean and the fan is seated fully.

Should You Buy It

Buy this if you need a budget-friendly quick replacement for a worn-out fan on a Hydro-Gear transaxle and you’re comfortable with potential 1-2 season life. Avoid if you run your mower commercially or in heavy debris—spend more on a reinforced OEM fan for durability.