2 Pack Replacement GX20818 GX21510 Mower Deck Spindle Bearing for John Deere L100 L120 L130 LA120 LA130 LA145 LA155 LA165 D110 D120 D130 D145 D155 D165 Models

What It Is

This is a 2-pack of replacement deck spindle bearings designed for select John Deere lawn tractors. The bearings support the mower blades, enabling smooth rotation for cutting. They’re intended for homeowners replacing worn or noisy spindles on 42-inch and 48-inch decks.

Fitment & Compatibility

Before buying, match your John Deere model and deck size. These bearings are listed for L100, L120, L130, LA120, LA130, LA145, LA155, LA165, D110, D120, D130, D145, D155, and D165 tractors, but only with specific OEM spindle housings (GX20818 and GX21510). Measure your spindle housing bolt pattern—these use a 2-bolt rectangular flange (3.5-inch center-to-center). Check that your deck uses a 1-inch diameter shaft and 1-inch inner bearing bore. If your spindle housing is a different design (e.g., square 4-bolt or smaller shaft), this won’t fit. Always verify your model’s OEM part number via the deck serial tag—don’t rely solely on the tractor model.

Key Things to Know

• Quality concerns: The 1.0-star rating (1 review) suggests potential issues—poor materials, premature wear, or loose tolerances. Expect lower durability than OEM (John Deere AM137813 or AM142083).
• Installation difficulty: Medium. Requires removing the deck, unbolting the spindle housing, pressing out the old bearing, and pressing in the new one. A bearing press or socket and mallet are needed. Grease the new bearing before install.
• Common gotcha: Many aftermarket bearings fail quickly if the spindle housing is bent or the blade is unbalanced. Inspect the housing and blade hub for damage first.
• Pack contents: Two bearings, no hardware or seals. You’ll reuse your existing bolts and dust caps.

Should You Buy It

Only if you’re on a tight budget and comfortable with potential early failure or inconsistent fit. For a reliable repair, spend more on a known OEM or higher-rated aftermarket spindle assembly (often $25–$40 each) that includes the housing and bearings pre-assembled. This 2-pack is a gamble—skip it if you need long-term dependability.