Length
Centerline length measurements are 3 dimensional measurements. The 3 dimensions are the following
- Length, the distance between 2 points when the height is parallel to the center plane.
- Height, the measurement is parallel to the datum plane.
- Width, the measurement is parallel to the center plane.
Show the horizontal width and length dimensions of the underbody from the bottom of the underbody. Show the vertical dimensions from the side of the underbody. Use the datum plane as a base for all vertical, height, measurements.
Scheme 13
The vertical body 0 line is a line drawn through the frame either at the forward or rearward torque box area of the frame.
Frames
The frame structure is independent of the body. The full frame extends the entire length of the vehicle. It supports the engine, transmission and the body. The suspension supports the weight of the frame. The metal thickness of the frame varies depending on the application and could be anywhere from 3 to 6 mm thick. Frames are covered with a wax base coating for rust protection.
All frames have body mounts welded to the structure. Thick rubber insulators are positioned between the body mounts and frame of the vehicle. These insulators absorb normal road noise and vibration generated by the suspension.
The following terms are defined