Rust-Prone Areas.

TB 43-0213

distinguishing design characteristic of a channel is that it

requires replacement of the affected metal area. In

is open-ended. Insides of all channels should be

some instances, such as in the M151 series 1/4-Ton

trucks, rust repair kits are available. For the most part,

cleaned, treated and rustproofed. Exterior sides are

however, maintenance personnel should refer to the

cleaned, treated, primed and painted.

vehicle-specific TM for replacement parts.

g. Stage 3 and Stage 4 rusted metal parts classified

as unserviceable should be removed. Adjacent areas

should be thoroughly cleaned of any rust, oils, or

chemicals before replacement parts are installed.

NOTE

Army policy requires that all accessible

under surfaces to be rustproofed must also

be cleaned, primed, and painted. This

additional barrier of paint will provide

greater protection to the metal.

h. Once the metal has been thoroughly cleaned,

exterior surfaces must be primed and painted (see

TM 43-0139). All accessible under surfaces such as the

underbodies of cargo and dump trucks should also be

primed, painted, and allowed to dry before applying

TA504747

Figure 2-6. Channels.

rustproofing material. Surfaces that are not readily

accessible for painting, such as boxed-in areas, are

(2) Rubrails (see Figure 2-7). Rubrails are

rustproofed only.

channels serving as both support members and as

structural protection for the vehicle body. The

i. After the affected surface has been prepared,

refer to the vehicle-specific chapters of this technical

horizontal crossmember trimming the tops of all cargo

bulletin for final rustproofing instructions (see Chapters

sides and tailgates are rubrails.

4 through 22).

(3) Stiffeners (see Figure 2-7). Stiffeners are

boxed-in or solid support members found in the

tailgates of all cargo trucks. Stiffeners strengthen the

2-5.

Rust-Prone Areas.

component to which they are attached. Solid stiffeners

as found on most 2 1/2-Ton cargo trucks present little

a. This technical bulletin provides specific rust-

difficulty regarding rust. Boxed-in stiffeners found on

proofing instructions for most tactical vehicles as well as

all 5-Ton trucks, however, are prone to trap moisture.

several commonly used trailers (see Tables 1 1 and

1-2). Application of rustproofing instructions can be

(4) Pockets (see Figure 2-8). Pockets are

applied to all vehicles. To assist in adapting such

tube-like designs such as the stake pockets used to

instructions, this paragraph provides a list of rust-prone

areas that are found in the design of most vehicles.

install the troop seat and side racks of cargo trucks.

Users are encouraged to recognize such areas and

Pocket designs are typically fully open at the top of the

understand why such areas are prone to rust. Finally,

tube. The bottom of the tube most often has a means of

users are encouraged to apply the principles of

drainage from the tube. This is not always true or

rustproofing to all vehicles and trailers using this

adequate, which makes pocket designs very vulnerable

technical bulletin as a guide. The following are likely

to rust as a result of trapped moisture.

areas for rust development:

(5) Tube Rails (see Figure 2-9). Tube rails

(1) Channels (see Figure 2-6). A channel is an

such as window frames of fold-down type windows or

open-ended design. It maybe square or C-shaped, such

the pillars of stationary windows are especially rust-

as the rubrail support members of cargo and dump

prone due to the boxed-in design and the thin gage met-

truck sides and tailgates, or an inverted U-shape found

al most often used in their construction.

in the understructure of M191 series trucks. The

2-5