5th/6th Driven Gear Cluster TY856 6MT Ratio 0.891/0.707

5th/6th driven gear for 6-speed manual transmissions with trans ID codes starting with "TY856".  Early models use a wide keyway (10mm wide) and later models use a narrow keyway (7mm wide).  An adapter key to install the narrow key gear cluster on a wide key shaft is available separately on this website.  This gear is for long ratio applications including our RST-F145Kit (2nd-6th) gear set.

Optional REM ISF© (superfinishing) treatment.  ISF is a precisely controlled treatment that reduces surface roughness left from the machining processes thereby improving reliability, reducing friction, and all but eliminating break-in requirements and the resulting swarf.  Ideally, we recommend treating both contacting gears (drive & driven sides) for optimal results.  Adding ISF processing may increase ship time by as much as a week.

Gears may need to be replaced due to gear tooth failure or damage to synchronizer dog teeth.  The peaks of the synchro dog teeth should be sharp and without any noticeable burrs.  Damaged synchro dog teeth due to gear clash or missed shifts will reduce the shift performance and severe damage can cause gear lockout or prevent gear disengagement.

Other possible sources of gear failure are overheating due to lack of oil supply, damage to bearing race surface resulting from bearing failure, or thrust surface wear due to heavy loading and/or lack of lubrication.

Gear Ratio: 0.891 (5th) / 0.707 (6th)

Tooth Count: 33 / 29

Manufacturer Part No:

• 32364AA100 Narrow Key (Legacy Spec B)
  
• 32364AA*** Narrow Key (Forester STI) ... MY04-06 require adapter key