5-4. UPPER COUPLER ASSEMBLY REPLACEMENT (Con't).
DO NOT perform task unless tank is empty and wheels are chocked. If tank
is full, landing gear could collapse when front of semitrailer is lowered.
Damage to semitrailer or serious injury or death to personnel will result.
Position a floor jack (1) directly
under kingpin (2) at upper
coupler assembly (3). Raise floor
jack to full height.
Operate landing gear and lower
front of semitrailer until kingpin
(2) contacts floor jack (1).
Upper coupler assembly (3) is
heavy and awkward to handle. Use
caution, provide adequate sup-
port, and use assistance during
removal. Failure to follow this
warning may result in serious in-
jury to personnel.
Centermost bolts (6) on each side
of upper coupler assembly (3)
should be removed last.
(3) Remove 14 locknuts (4), bolts
(6), and washers (5). Discard
Carefully lower upper coupler as-
semitrailer. Remove from floor
Remove all traces of old mylar tape from mounting surfaces of upper coupler assembly to