The trucks are very exspensive, ones like in this pic are in the millions. Stuff in this range of price is generally repaired for a long time and kept in service for decades and is built more like industrial equipment. There isnt much on the truck that cannot be replaced. They are also suprisingly strong. This one is probably rated to carry about 80 tons, which means the truck probably weighs atleast as much. So you are looking at 160k ibs before being loaded and over a quarter million pounds when loaded. Every part of that truck has to exceed the shock forces of that at several gs so you can imagine how much of a bitch it is to take off a skid plate or something. You better eat you wheeties. Thats why replacing them is more of a long term process. We have a bunch of 40 ton and some heavier rock trucks like this. We replace them about every 10-20 years but may keep them longer if they are in decent shape. There is no hard limit on their lifespan and generally newer equipment is worse and weaker because of emmisions and saftey equipment. These trucks are more like mining trucks. They usually work in big mines since you have to take the truck apart to transport them on highways or move them on rail. They are not usually worth hauling for smaller jobs because you have to find someone who is willing to assemble and disassemble them.

Many pieces of equipment half this size will have engine replacments, and other major systems replaced in its lifetime. Sometimes axles, transmissions, even cabs and stuff. Companies usually keep some as spares when they get severly damaged to use as parts. This one is probably not damaged as bad as it looks unless they left the engine running after it flipped. The bed is thick steel.