Bully Dog offers its gauge tuner for Detroit, Cummins, Caterpillar, Paccar, and Mercedes heavy-duty engines. The gauge tuner changes the electronic tuning characteristics of the engine management system in order to optimize performance and reduce fuel use. Engine characteristics the tuner manages include turbo boost pressure, RPMs, coolant temperature, air flow, and fuel rail pressure, Bully Dog stated. The tuner can also take into account vehicle characteristics such as vehicle load. The tuner can save 8 cents per mile, according to Bully Dog.

In addition to monitoring engine performance, the unit provides four functions overall, including engine tuning, monitoring engine function, acting as a performance gauge, and acting as a diagnostic device, Bully Dog stated.

The gauge tuner is compatible with a range of vehicles and, when a vehicle is no longer in use, can be transferred to another vehicle and reprogrammed so it’s compatible, according to the company. The tuner must remain in the vehicle while it’s operating in order to manage engine characteristics.