An exhaust cleaning system for motor vehicles, especially a diesel exhaust cleaning system for medium to heavy utility vehicles. The exhaust cleaning system has an exhaust muffler (1), a catalytic converter (2) and an exhaust particle filter element (3). The exhaust muffler (1), the catalytic converter (2) with a U-shaped tubular urea injection element (4) arranged upstream and an exhaust particle filter element (3) are integrated in a common housing and designed as a structural, functional unit.