We have a long history of building, maintaining and repairing pre-selector gearboxes. The process begins with a complete strip down of the gearbox to asses any faults or wear. Depending on gearbox type we will either have parts such as gears and drums manufactured new or sourced from our large in house stores unit. The brake bands are relined and then precision machined to each drum for perfect engagement. The gearbox is then reassembled with care taken to check the correct clearances and end-float in the gear train. Modern seals and sealant are used to reduce any oil leaks that may occur. Upon reassembly the gearbox is set up and tested on a dyno-rig where final adjustments are made to ensure optimum grip.