Five
Three - the two drive axles, and the steer axle.
Tandem by definition is two. So tandem axle is two axles. Example would be a tractor trailer having two axles next to each other is a tandem axle.
A tandem truck is a truck with two drive axles.
It has two drive axles.
The average tandem axle truck can carry about 12 cubic yards of soil. Generally, a tandem axle truck has three axles.
A dump truck with two drive axles.
There's different weight ratings. For trailers, you can have fixed or sliding tandems, or you can have spread axles.
The "tandem" part means it has two drive axles, although it is possible for a tandem truck to be a 6x2 vehicle, and have only one of those be a live axle.
This is typical for tandem axle trucks. Two axles are live axles, and the driveshaft goes into a power divider. The power divider supplies power to both axles.
A tandem dump truck is as normal as any other dump truck. Tandem simply indicates that it has two drive axles (as opposed to a single axle, which only has one). A tandem dump is typically allowed to gross at 54,000 lbs. From there, some dump trucks have additional axles (lift axles) which allow them to haul more weight. They're named in accordance with the number of axles behind the cab (i.e., not including the steer axle). So a tandem dump with a single lift axle would be referred to as a tri-axle, with two lift axles it would be referred to as a quad axle dump, with three lift axles it would be referred to as a quint axle dump.... at four lift axles, they're typically referred to as 'centipedes'.
Tandem axles are connected by spring Multi axle trailers Shipyard Transporters