A driver helper is a person who assists the driver of a commercial truck in loading and unloading cargo, performing basic maintenance, and other tasks.
Driver helpers work under the direct control of the truck driver and must meet strict criteria for licensing and training.
Driver helpers are not allowed to operate a commercial truck without a truck driver's authorization and supervision.
Driver helpers are sometimes referred to as truck loaders.
However, that term is also used in transportation industries other than trucking.
In trucking, a truck loader is a person who climbs into the cargo bed of a truck to help lift and load the cargo.