50 Inch Mower Deck Rebuild Kit for Cub C vs Ariens / Gravely Lawn Mower 42" Mulch Ki

50 Inch Mower Deck Rebuild Kit for Cub Cadet MTD RZT 50 RZT 50VT RZT50 ZT50 ZT 50 Troy Bilt Mustang XP 50 Lawn Mower Spindle 618-04126 Blade 942-04053 Belt 754-04044 Idler 956-04129
50 Inch Mower Deck Rebuild Kit for Cub Cadet MTD RZT 50...
$119.99
★ 4.2/5 · 36 reviews
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Ariens / Gravely Lawn Mower 42" Mulch Kit Part# 71513900 Fits ZT-X and IKON X 42" Deck
Ariens / Gravely Lawn Mower 42" Mulch Kit Part# 71513900...
$205.95
★ 3.9/5 · 36 reviews
Read full review →
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Quick Verdict

Choose the Cub Cadet 50-Inch Mower Deck Rebuild Kit if you need to restore a worn-out cutting deck on a compatible RZT model and want a complete set of replacement parts at a lower price. Choose the Ariens/Gravely 42-Inch Mulch Kit if you want to convert an existing ZT-X mower to mulching and prefer a dedicated, brand-specific accessory for a narrower deck.

Side-by-Side

Feature Cub Cadet 50" Rebuild Kit Ariens/Gravely 42" Mulch Kit
Price $119.99 $205.95
Primary Function Deck rebuild/repair Mulching conversion
Cut Width 50 inches 42 inches
Best Yard Size 1–3 acres ½–2 acres
Rating 4.2/5 (36 reviews) 3.9/5 (36 reviews)

Where Cub Cadet Wins

Lower cost. At $119.99, the Cub Cadet kit costs about $86 less than the Ariens/Gravely mulch kit.

Larger cutting width. A 50-inch deck covers more ground per pass, making it better for larger lawns and reducing mowing time.

Rebuild value. This kit is designed to replace worn spindles, pulleys, blades, and hardware on aging RZT 50, RZT 50VT, and RZT50 mowers. If your deck is rattling or cutting unevenly, this kit can restore performance at a fraction of the cost of a new deck.

Higher user rating. A 4.2 average from 36 reviews suggests most buyers are satisfied with the parts fit and quality.

Where Ariens Wins

Purpose-built mulching. The Ariens/Gravely kit is specifically engineered to convert a 42-inch ZT-X mower into a mulching machine. It includes a baffle kit and mulch blades designed to recirculate clippings for finer cutting and better nutrient return.

Brand compatibility. As a genuine Ariens/Gravely part (71513900), it ensures exact fitment and warranty compliance for those mowers. No guesswork about part dimensions or bolt patterns.

Smaller yard efficiency. A 42-inch deck is more maneuverable in tight spaces, gardens, and around obstacles. For lawns under 2 acres, the narrower width can be an advantage.

Mulching focus. If your primary goal is converting to mulching (rather than rebuilding a worn deck), this kit provides the specific parts needed without extra components you won’t use.

Which Should You Buy

Buy the Cub Cadet 50-Inch Mower Deck Rebuild Kit if you own a Cub Cadet or MTD RZT 50, RZT 50VT, or RZT50 with a worn deck that needs new spindles, pulleys, or blades. It is the better value for repairing a 50-inch deck on a larger property (1–3 acres) where cutting width matters most.

Buy the Ariens/Gravely 42-Inch Mulch Kit if you own a ZT-X model and want to convert it to mulching. It is the better choice for smaller lawns (½–2 acres) where fine clippings and deck maneuverability are priorities, and you are willing to pay more for a guaranteed fit and dedicated mulching function.