Albins Gear Slider / Sleeve - GR6 / R35 GTR Transmission
This is a MUST for the earlier revision GR6 transmissions!
The 2009 - 2011 GTR (CBA) gear sliders have a known issue with the engagement teeth on the slider breaking off. When this happens, the shrapnel can collect within the hub causing the transmission to be stuck in gear or even be blocked out of gear. If the transmission becomes blocked out, it will still continue to try to engage the gear. This puts a lot of stress on the shift forks, as the pistons will repeatedly try to move the fork into gear, which can easily cause the fork to break.
Other scenarios with having the engagement teeth on the slider breaking off include valve body / valve body piston damage. The piston solenoids use a magnetic coil to allow them to float within their chamber. Because the solenoid is magnetic, a broken slider tooth can easily be drawn into the piston chamber and score up the piston walls, causing the assembly to not work.
In essence, having an older style of slider / sleeve causes a huge reliability issue within the transmission. It is not a matter of IF the old style slider will fail / break, but more along the lines of when.
The earlier revision have short engagement teeth and the revised slider uses full length engagement teeth. The pictures compare the earlier to the revised style.