• 31.-1 19
• 31.00 General91
• 31.10 Trailer coupling, fifth-wheel coupling52
• 31.11 Trailer coupling - mechanical system1
• 31.19 Trailer coupling - electrical system11
• 31.20 Subframe1
• 31.30 Frame, lateral underride guard22
• 31.35 Axle/engine sub-frame4