Used Main Gearcase (Powersports) 1990–2019

The main gearcase is the primary transmission housing on a powersports machine -- ATVs, UTVs, motorcycles, snowmobiles. It contains the gear set, shift forks, bearings, and shafts. The case itself is typically cast aluminum and can crack from impact, stripped threads, or a bearing that spun in its bore. A cracked case causes gear oil leaks that rapidly destroy the internals. A case with damaged thread inserts or bearing bores can't properly retain the components inside. Replacing the case is a major job, but far cheaper than buying a complete new transmission assembly. Used OEM cases from low-hours donor machines are the most practical source for this level of repair. The case must match your exact transmission configuration -- gear layouts vary even within the same brand across model years. Redline carries main gearcases from 4 sellers covering powersports machines across 8 makes including Chevrolet, Honda, Land Rover, Lexus, Infiniti. Confirm the case half orientation and bearing bore sizes before purchasing. Filter by brand, year, and model.