New aftermarket replacement air cylinder for Mack air assist clutch. Fits Mack part #21131322. Full stainless steel construction.

I stock the 3 port air cylinder as well. Search my store for “Mack air cylinder “

This air cylinder IS a direct replacement for mack air assist clutch air cylinder with 2 ports (1 port on each end). This is NOT a direct replacement for air assist clutch air cylinders with 3 ports. The third port (the one in front connected by a hose to the one in back) is only a vent for the boot and does not have anything to do with the operation of the air cylinder, but the diameter of the nose and boot on the 3 port cylinder is larger than that of the 2 port cylinder. Meaning the rubber boot from the 3 port cylinder will not fit correctly (too large) on the 2 port cylinder. Mack used the same part number on both cylinders.

Fast free Priority Mail Shipping. Need it faster?  Priority Mail Express $35. Message me for details.