Replacement of the WABCO System Saver Air Dryer Desiccant Cartridge

P4 MM 42.10; 5th Generation Cascadia MM
Notice: The WABCO System Saver air dryers can use either a standard or oil coalescing desiccant cartridge. When replacing the desiccant cartridge, it is very important to use the same type of cartridge that was originally installed on the dryer. Oil coalescing cartridges can be used in any application, but require more frequent service intervals (every 1 to 2 years instead of every 2 to 3 years for a standard cartridge). Do not replace an oil coalescing cartridge with a standard cartridge, as this may result in contamination and malfunctioning of downstream air system components.
Note: The following instructions apply to the System Saver 1200, 1200 Plus, and Twin air dryers.

See Fig. for cartridge replacement.

  1. Drain the air system.

    1. Seal

    2. O-Ring

    3. Air Dryer Base

    Fig. 1, Desiccant Cartridge Replacement

  2. Using a strap wrench, turn the desiccant cartridge counterclockwise and remove it.
  3. Remove and discard the O-ring.
  4. Clean the top surface of the dryer base with a commercial cleaning solvent.
    5. Important: If the air dryer base is damaged, preventing a tight seal, replace the air dryer.
  5. Using a multipurpose, high-temperature grease that resists water, steam, and alkali, lightly coat the surfaces of the new O-ring and the dryer base. Install the O-ring.
  6. Thread the desiccant cartridge onto the dryer base (turn clockwise). When the seal contacts the base, tighten the cartridge one complete turn more. Do not overtighten.
Note:
Parent topic: Brakes
Document Number: 0000103287
Manual Publication Date: 2025-07-14
Topic Publication Date: 2026-05-06