ADJUSTING PLATFORM HEIGHT (CONT)
DO NOT leave semitrailer unattended with suspension raised to highest position.
Outside temperatures can cause thermal expansion of the hydraulic fluid and
create unwanted pressure build up without means to relieve pressure. Thermal
expansion can cause premature failure or severe damage to equipment.
DO NOT move semitrailer with suspension raised to its highest position.
Individual bogies may sustain excess load which may result in premature cylinder
failure or severe damage to equipment.
If the platform becomes uneven during adjustment, release valve handle for
platform area that is leading the adjustment while holding the other two valve
handles. Once the platform evens out, continue to operate all three valve handles
to adjust platform.
f. To raise platform, simultaneously pull up and hold handles of front curbside (4), front streetside (5), and rear (6)
suspension valves. Once platform reaches highest position, stops, and APU rpm decreases, release all three
DO NOT allow suspension to completely bottom out in the lowest position (unless
otherwise directed by specific operation or maintenance procedures) or individual
bogies may sustain excess lead and result in premature cylinder failure or severe
damage to equipment. To ensure proper suspension pressure equalization, lower
platform until the shortest (compression) suspension cylinder piston still has 1
inch (2.54 cm) of polished chrome exposed.
g. To lower platform, push down and hold rear suspension valve handle (6). Once rear of platform starts to lower,
push down and hold handles of front curbside (4) and front streetside (5) suspension valves. Once platform
reaches lowest suggested height, release all three suspension valve handles.
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