The front end has twin I beams, coil springs. Here is a pic of the truck. It came as a flatbed. I found out that not all F350's have the same springs in the rear.Yes, the f350 dump truck I worked on had that beefed up frame. Since you have a cab and chassis truck, your truck is completely oddball from the cab rearward compared to a regular dually pickup. The frame is more narrow, the rearend housing is more narrow, you have a large stack of leafs in the rear but they are narrow also. A pickup bed will not fit on your frame if you ever had that notion.
The little f350 dump I worked on was 4x4 also. If you take the other guys advice and install a tranny and transfer case, then you will 1/2 of the way to 4x4. Later on you could swap the front axle and have 4x4, though I am not sure what your front suspension looks like now. Does it have leaf springs or coils up front?
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