As summer approaches and temperatures heat up across the country, some components on Class 8 trucks need extra attention to prevent unscheduled maintenance or costly fixes down the line. Chris Hough, vice president of maintenance design and engineering at Penske Truck Leasing, said focusing on certain items when temperatures increase can improve uptime and increase driver satisfaction.
“A lot of the maintenance is the same year-round, but there are certain maintenance items, especially the heating, ventilation, and air conditioning (HVAC) system and tire pressure, that are important in the summer,” Hough said.
Air Conditioning System Maintenance: Inspecting the HVAC system, including circulation air filters and ensuring the AC system is cooling as designed, is important for driver comfort and safety, Hough said. Demands on air conditioners increase in summer months, and the units should be checked regularly. Technicians need to ensure the engine fan/clutch is activated and engages properly when the A/C system is turned on. In addition, the A/C system typically interfaces with the vehicles’ electronic systems and controllers, which means that abnormal operation conditions within the A/C refrigerant subsystem could trigger fault codes that need to be investigated, repaired and cleared before the vehicle is placed back into service. This is also a good time to service or replace the cabin filter.
Truck Tire Maintenance: Proper summer tire pressures improve safety as well as tire life and fuel economy, and tires need special care when temperatures increase. “Maintaining correct tire pressure during the summer months will help reduce over-the-road-tire failures,” Hough said.
Tires tend to run hotter and wear faster in the warm weather, and the tread portion of the tire becomes softer in the summer months. That makes tires more susceptible to punctures from road debris.
To help mitigate the risks tires face, tire inflation pressure needs to be checked with an accurate tire pressure gauge. Because tire pressure increases as temperatures rise, there is a risk of over-inflated tires in the summer. When air pressures are inaccurate, tires flex in ways they weren’t designed to, changing the shape of the tire’s footprint. That not only decreases fuel economy but also creates irregular wear patterns and reduced tread life. Also, underinflated tires build up excessive heat, potentially causing premature failure.
Cooling and Electrical System Maintenance: During the summer, it’s critical to make sure a truck’s engine radiator, EGR coolers and transmission cooler operate properly to maintain the correct engine and transmission temperatures. Inadequate or improper service of cooling and electrical systems can lead to heat-related failures during the hot weather. Penske checks cooling systems on every preventive maintenance inspection.
Electronic component failures can be caused by damaged or missing heat guards, heat shields or heat deflectors, especially within those components found near the exhaust system after-treatment devices. Excessive heat can also melt or make the plastic electrical connectors brittle, leading to electrical malfunctions caused by poor connections at the electronic control units, sensors and solenoids that control various vehicle systems.
APU Maintenance: Auxiliary power units also require some special attention during the summer. Diesel-powered APUs are like mini engines with belts, lines and AC compressors that should be checked. An electric, battery-powered APU is integrated with the cab air conditioning and should also be checked over to ensure it is functioning properly.
Refrigeration Unit Maintenance: Warm temperatures mean the reefer units on refrigerated trailers face higher demand. To ensure they run properly as outdoor temperatures increase, carriers should inspect them regularly.
Battery Maintenance: Battery maintenance is not seasonal; a solid, year-round battery maintenance program will pay dividends.