Car manufacturers are constantly improving and refining their cars and the parts that make them up. There can be some benefits for owners to fit the later parts to their earlier cars. Or sometimes this happens, when the earlier part fails and the easily available replacement is a later part, which may even be a used one from a car that is broken up for parts.
The AYC rear diffs on Mitsubishi Lancer Evolutions 4~9 are a classic example of this. These parts do fail and often people make the later parts fit their earlier cars. Which is fine, until you decide to modify or repair the newly fitted assembly – as you may not be ordering the correct parts to match the components now fitted to your car.A very popular modification for GSR cars with AYC fitted at the rear, is to improve the AYC with the addition of a Cusco LSD (the Cusco LSD replaces the open diff. controlled by the AYC’s hydraulic clutch. The AYC can be retained or removed/disabled).
Evo 4~6 (CN9A/CP9A) were all very similar, whilst the Evo6TM~9 (CP9A/CT9A) had different sized bearings – the casings being different.
The basic details, so you can easily identify the units are as follows:
CN9A/CP9A
LSD-148 for old version: Side Bearing size ID60mm (OD85mm)
CP9A TM/CT9A
LSD-448 for new version: Side Bearing size ID67mm (OD92mm)
Tags: ayc, cusco, diff, differential, evo, lancer, lsd, mitsubishi
hi there
i was reading this about the ayc diff ! so the cusco diff fit to ayc ? or you must have rs diff ?
cause i’m interisted in it !
thanks mike