Dodge gave you several options on front suspension. Most trucks could be had with a light duty, or the heavy duty suspension, depending on what box was checked when the truck was ordered. There was really little rhyme or reason other then checking the desired box on the order form. Most times, the suspension and the steering parts are tied together, seldom did one get heavier unless the other also got heavier, but there are those few examples that didn't follow the suit.

D100 is a light duty nearly car suspension. It generally came on slant 6 or 318 base model trucks.

D150 is the heavy duty version for a 1/2 ton, and resided under most 1/2 ton trucks. These featured larger brakes, and a higher capacity springs. They also had larger ball joints and tie rods.

D200 is a light duty 3/4 ton truck. It was basically a heavy duty 1/2 ton with 8 bolt rotors and 8 rear brakes with a Dana 60 rear axle assembly.

A D250 was the heavy duty 3/4 ton truck, often referred to as a "Camper Special". It had larger brakes, heavy springs, and larger suspension parts, it was a heavy duty truck.

A D300 is a one ton truck. It could be had with single rear wheels or dual rear wheels. This was the same basic truck as the Camper Special 3/4 ton with the option of getting dual wheels. There was also a heavy duty 1 ton that had big truck underpinnings, but those were pretty rare. Most guys that wanted a heavy duty 1 ton bought a big truck instead.

To add complexity, any truck could be ordered with rear overload springs, they were additional springs spaced above the original spring pack and seated against brackets on the frame when the load reached a certain point. Usually, but not always, when overloads were ordered, the truck got the next up spring and suspension package.

To make things even more fun, somewhere along the course of truck building, Dodge eliminated the extra size listings and went with a 150, a 250 and a 350, but any could have had the light duty suspension or the heavy duty suspension and steering components.

A truck with a "D" prefix is a 2 wheel drive. A truck with a "W" prefix is a 4x4 truck. For a while, Dodge decided to call the D trucks 150, 250, and 350, but the same version of the W trucks were 100, 200, and 300. Are we having fun yet?

So in answer to your question regarding brake rotor and other parts swapping between a 5 bolt and an 8 bolt, the correct answer is: YES, and NO! Some parts from a heavy duty 1/2 ton and a light duty 3/4 ton will swap, you just have to know which parts are on which truck.

Fortunately, Dodge often referred to truck suspension as a weight capacity, two trucks of the same weight capacity should have the same suspension. The nice thing is, one doesn't have to look very hard to see if the parts are the same size, its pretty obvious a light duty version is very much lighter then the heavy duty version. Gene