NHTSA recall 97V151000
Service brakes, air › Supply › Low pressure warning › Switch
Western Star Constellation and 1 more
The defect
Vehicle description: heavy duty 6X4 trucks equipped with either hendrickson rt/rs series suspensions or chalmers 800 series suspensions, with a wheel base greater than 250 inches, and western star's air '96' air brake system without anti-lock brakes. these vehicles do not meet the air brake release time required by fmvss no. 121, "air brake systems."
The risk
Air brake release time may be longer than anticipated by the operator increasing the risk of a vehicle crash.
The remedy
Dealers will install an in-line quick release valve in each of the drop lines to the rear most brake chambers.