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U.S. 888-725-9355
Canada 800-387-3889
INFORMATION NEEDED TO SELECT THE RIGHT ASA
ONCE THE CLEARANCE AND HANDED ISSUES ARE DETERMINED, ASA SELECTION IS EASY! YOU JUST NEED THE
FOLLOWING INFORMATION ABOUT THE VEHICLE APPLICATION:
1. SPLINE DIAMETER AND SPLINE COUNT OF THE CAMSHAFT
2. ARM LENGTH
Distance from center of cam to the main clevis center hole.
3. CLEVIS CONFIGURATION
Clevises are either straight or offset. In some cases a helper spring will be needed for use
with the clevis. This will occur with the smaller chamber types 9 and 12.
4. CLEVIS THREAD SIZE
This will correspond to the air chamber push rod. Generally, chamber sizes 9, 12 and 16
will use a 1/2”-20 thread clevis, and chamber sizes 20, 24, 30 and 36 will take a 5/8”18 thread clevis. All aftermarket
clevises are threaded. The “quick connect” clevis is for OEM production assembly use only.
5. THE AIR CHAMBER SIZE AND TYPE OF BRAKE
The Meritor ASA adjustment is precision tuned by the piston in the
actuator adjusting sleeve. There are two pistons of differing lengths depending upon the chamber application and will
impact two things:
A) When the actual brake lining
adjustment
is necessary
B)
Adjusted Chamber Stroke
length visible to the operator