3.3 Materials. Materials shall be as specified herein and in referenced specifications and
drawings. Material shall be free of all defects that might affect serviceability and functions of the
finished product (see 4.1.2 and 6.7).
3.3.1 Qualified products. The contractor shall be responsible for using all assemblies and
parts necessary in semitrailer construction that are listed as qualified products on the Qualified
Products List (QPLs) and those approved for inclusion on the QPLs. Assemblies and parts
determined as QPL items appear on the engineering parts list. The contractor manufacturing
inspection records shall specifically list all QPL items by part or drawing number, name of
supplier, and number and date of the QPL. When assemblies and parts are approved as qualified
products but not yet listed on QPLs, the contractor shall list the products by number and date of
the approval document with the name of supplier (see 4.1.2).
3.3.2 Fungus resistant product. Materials required to resist fungus shall meet the requirement
of MIL-STD-454, Requirement 4 (see 4.1.2).
3.3.3 Flammable materials. Flammable materials shall not be used unless the materials are
provided with suitable protection to prevent hazard (see 4.1.2).
3.3.4 Ozone resistance. When rubber components are required to be ozone resistant, the
degree of resistance shall be as specified in applicable specifications or drawings (see 4.1.2).
3.4 Construction. Trailer components, subassemblies and assemblies shall be fabricated and
assembled into a complete trailer in accordance with applicable drawings (see 2.1.2). Guided
missile transporter M976 is manufactured from the M974 base trailer and from the conversion kit,
Drawing 10252280. Large repair parts transporter M1033 is manufactured from the M974 base
trailer and from the conversion kit, Drawing 11455333. All parts, assemblies, and subassemblies
requiring identification shall be identified in accordance with MIL-STD-130. The fabrication and
manufacture of equipment shall be executed in a manner commensurate with the intended use of
the end item and accepted Government standards and specifications delineated herein.
3.4.1 Wheel bearing seals. When fording or operating in mud, sand, or snow, seals shall
prevent entrance of foreign matter into bearings. Water contamination of wheel bearing lubricant
after fording operations, shall be not more than 2 percent by volume. All bearing seals shall
prevent leakage of lubricants from the bearings (see 4.8.2).
3.4.2 Electrical system. The trailer shall be equipped with a 24-volt electrical lighting and
signaling system in accordance with applicable drawings and provide connection to a suitable
towing vehicle 24 volt system (see 4.8.3).
126.96.36.199 Electrical circuits. Electrical circuits shall maintain continuity from end to end
without evidence of internal or external shorts during all trailer operating conditions (see 4.8.3).