2026 Blue Bird Vision School Bus TSBs

limitations of the mechanical switch. As a result, a preventative maintenance adjustment procedure is necessary and, at times, settings can be difficult to achieve.

Condition:Chassis web fractures in or around the vicinity of the LF shock mount Root Cause Identification and Justification: FEA modeling shows elevated regions of stress in proximity of the upper fastener hole for the LH shock mount resulting from several external influences. The highest stress stemming from shock extension forces in curb hop scenarios. Bearing in mind the absence of this failure mode on standard floor chassis designs with substantially higher usage, the projected stress in this region of 4582 PSI is used as an objective bench mark of the acceptable upper limit. Two corrective solutions are being executed as pragmatic countermeasures to correct this failure mode, based on the severity and frequency of the crack, if present. Repair plate 1 being the latest evolution. FEA analysis & ref chart below Installation of this repair plate decreases the stress in this region to less than the standard floor chassis baseline allowing us to predict this solution to last the expected life of the chassis.