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All Technical Service Bulletins for Brake Proportioning/Combination Valve:|8585 > < Height Sensing Brake Proportioning Valve - Adjustment
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Cut Tang From Adjustment Gauge

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Cut gauge tang from body of the adjustment gauge to allow the valve assembly to rotate freely (Figure No. 3).

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Lower vehicle and test brakes.

PARTS INFORMATION

Model

P/N

Description

Code

Color

C20906

14061394

Gauge

A

Green

K20906

15548904

Gauge

E

Yellow

Brake Burnishing

On dry clean level roadway, accelerate to 55 mph, observe traffic following, and when it's clear:

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Apply brakes at a deceleration rate of 8 ft/sec/sec until vehicle speed is 25 mph. A decelerometer must be used to achieve the proper deceleration
rate.

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Repeat this procedure at 1 mile intervals 15 times.

Decelerometers are available from various sources, one of which is:

Ammco Tool Company 2100 Commonwealth Avenue
N.

Chicago, IL 60064

All Technical Service Bulletins for Brake Proportioning/Combination Valve:|8585 > < Height Sensing Brake Proportioning Valve - Adjustment