Modular frame structure for off road vehicle

1. An off-road vehicle comprising:

left and right identical, straight frame rails arranged parallel to each other, each of the left and right frame rails including a front portion, a middle portion, and a rear portion;

a plurality of identical adapters mounted to each of the left and right frame rails and positioned along the length of the frame rails at selected positions within each of the front portions, middle portions, and rear portions;

a front frame module mounted to the adapters in the front portions of the left and right frame rails;

a rear frame module mounted to the adapters in the rear portions of the left and right frame rails;

an occupant frame module mounted to the adapters in the middle portions of the left and right frame rails;

a front suspension assembly mounted to the adapters in the front portions of the left and right frame rails; and

a rear suspension assembly that is identical to the front suspension assembly, the rear suspension assembly mounted to the adapters in the rear portions of the left and right frame rails.

2. The off-road vehicle of claim 1 , further comprising:

a prime mover;

a steering assembly including a steering column, a steering wheel mounted to the steering column, a steering transmitter operable under the influence of rotation of the steering column, at least one tie rod interconnecting the steering transmitter with at least one of the front suspension and rear suspension;

a front end assembly mounted to the front frame module, the front end assembly including a front body, a dashboard, and pedals for control of the prime mover, the front end assembly supporting the steering column;

a cargo bed assembly mounted to the rear frame module; and

at least one occupant seat mounted to the occupant frame module to support an occupant of the off-road vehicle within reach of the pedals and steering wheel.

3. The off-road vehicle of claim 1 , wherein the front and rear frame modules each include a pair of identical suspension hoops having first and second feet, the feet of each suspension hoop being mounted to adapters mounted on one of the left and right frame rails.

4. The off-road vehicle of claim 1 , wherein the front and rear suspension assemblies each include first and second suspension cross members that extend perpendicular to each of the left and right frame rails and are mounted to adapters on the left and right frame rails, each of the front and rear suspension assemblies further including left and right suspension assemblies mounted to the first and second suspension cross members.

5. The off-road vehicle of claim 1 ,

wherein each frame rail includes a base and a mating portion;

wherein each adapter includes a mounting surface and a receiving portion;

wherein the front and rear frame modules are mounted to the mounting surfaces of the adapters;

wherein the mounting surface of each adapter includes a clearance aperture;

wherein the receiving portion of each adapter includes a bottom wall defining a threaded hole aligned with the clearance aperture;

wherein a gap is defined between the bottom wall and the mounting surface of each adapter;

wherein each adapter further includes a fastener including a threaded end and a head; and

wherein each adapter is secured to a frame rail by extending the fastener through the clearance aperture and threading the threaded end into the threaded hole, such that the head of the fastener bears against the mounting surface and the bottom wall is drawn toward the mounting surface to decrease the gap.