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Long Stroke Brake Chambers
Watch your brake chambers! Most new vehicles are now being equipped with long-stroke brake
chambers.This allows more stroke than older models. You will find clamp type 20 and clamp type
16 long stroke chambers on the steering axles and clamp type 24 and clamp type 30 long stroke
chambers on other axles. Some of the type 30 chambers allow a three-inch stroke.
A long stroke brake chamber can be identified by the raised inlets, embossed etching on
the side of the chamber and/or a trapezoidal shaped I.D. tag indicating long stroke, and
the maximum stroke allowed.
The key advantage of the extra stroke available from the actuator's unapplied position to full
extension, is that it keeps brakes in adjustment longer, reduces out of adjustment citations and
improves brake efficiency.
All VENDORS advise to never install long stroke and standard stroke chambers on the
same vehicle. This can cause poor brake balance and timing.
When servicing these brake actuators, it is imperitive that strict attention is paid to the
components. These chambers have push rod stroke capabilites in excess of the standard
2.25" to 2.5" design. The components are unique, and include the following: (They are
identified as " Long Stroke"-"LS"-or"3"stroke")
•service diaphram
•service housing
•service pushrod
•complete piggyback
All Navistar 2000 & Newer Buses Now Have Long Stroke Brake Chambers With Square Ports. Long
Stroke Chambers Provide 17% More Stopping Ability On A Hot Stop!!
Long Stroke w/
Square Ports
Short Stroke w/
Round Ports
According to MGM, single chambers-service chambers also have the square ports, and show
pictures of the models to indicate this in the literature they provide. These pictures were scanned
from that catalog.
SPRING BRAKES