An exhaust system for an engine having a throttle is disclosed. The exhaust system may include an exhaust passage connectable to the engine, a particulate filter disposed in the exhaust passage, a sensor configured to generate a signal indicative of a total pressure differential across the particulate filter caused by soot and ash accumulation, a load actuator configured to selectively adjust a load on the engine, and a control module electronically connected to the load actuator and the sensor. The control module may be configured to determine a compensated pressure differential indicative of an amount of the total pressure differential caused by soot accumulation, a soot load of the particulate filter based on the compensated pressure differential, cause the load actuator to initiate a first engine load increase based on the soot load, track a time elapsed since initiation of the first engine load increase, and cause the load actuator to initiate a subsequent engine load increase when the time elapsed is greater than an elapsed time limit and the soot load is greater than a target soot load.