Features/FAQs
Over time, internal thrust washers thin out and loose needle bearings wear down, causing excess counter gear play and shaft vibration. This complete small parts hardware package replaces critical high-wear items during an extension or case overhaul.
Fitment Note:
- This kit fits GM 1963–1965 Muncie M20 transmissions only featuring the small bore 7/8" outer diameter countershaft pin. It will not fit later M21 or M22 units utilizing the 1" countershaft.
Doing a full rebuild? Don't drop fresh needle bearings onto pitted gears or worn sliders. Check our store for matching Muncie M20 7/8" brass synchronizer rings (WT297-14), complete high-density gasket sets, and performance extension housing seals.
OEM/Interchange Numbers: 304001, WT297-50, MGR-SP297-50, ZMSP297-50
Please confirm your diameter countershaft pin prior to purchase to ensure compatibility. |
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