A Matter of Degrees
Winterize now and keep rolling through the cold
By Homer Hogg, Senior Technical Trainer for TA and Petro
Winter is just around the corner and trucks don’t particularly like low temperatures. Metal parts, fluids and coolants just don’t move as smoothly when they are cold. Freezing moisture can decrease braking power. And the cooling system doesn’t do well either — metal contracts as the temperature dips so hose clamps get loose, which can lead to leaks. Fortunately, a few proactive steps can help you avoid costly downtime and control your maintenance costs.
Keep the power flowing
All good winter preparation programs must focus on your vehicle’s cranking and charging systems. Get your batteries load-tested now to ensure they will handle the high demand required to turn a diesel engine over during cold starts, and also keep the lights shining through those extra hours of darkness. Have the cables voltage drop-tested to ensure no hidden corrosion goes undetected and untreated.
A thorough visual inspection of all components will help you spot corroded or loose connections that may need attention. Also look for belts that are slipping due to excessive wear or a worn tensioner.
The belts must be in good working order or your alternator will slip, preventing the batteries from operating at a full charge. Not only will this keep your vehicle from cranking, but the alternator front bearing may overheat and that will cost you an alternator. Plus, an undercharged battery will sulfate — chemicals inside the battery separate and sulfur molecules coat the inner lead grids, basically plastering off these key elements that make the battery work. If that happens, you will most likely have to replace the battery.
Moisture doesn’t evaporate in the cold; it freezes. That can lead to serious problems in your brake system, which must be inspected for leaks and proper operation in preparation for winter. I recommend additional emphasis on the air dryer. This key part cleans and conditions the air that goes into the wet tank, where compressed air for the brakes is stored. A less-than-optimal performing air dryer can let that moisture build up and cause the air pressure gauge to read full even though it does not contain enough air volume to operate your vehicle safely. The dryer desiccant cartridge should be replaced according to the manufacturer’s recommendation or if you notice excessive moisture in your wet tank during your pre-trip inspection. In addition, a qualified technician should conduct a test of your purge system and air governor.
Too cold to cool off
Finally, let’s not neglect the cooling system. If you get your coolant hose clamps inspected and tightened, you will experience fewer cold water leaks and avoid costly breakdowns due to engine shutdown. Your cooling system should be pressure-tested to include your radiator cap. Maintaining the proper pressure on the cooling system is critical to controlling the heat load of the engine. A qualified technician should inspect the condition of the coolant to include its additive package. Often overlooked but certainly important is the condition of your cabin filter. In order to get clean, comfortable air from your heating system, the cabin filter must be clean and environmentally safe.
All of these steps are part of a standard winterization process, and are very effective throughout the season. When I was a fleet maintenance director, I could look at my maintenance running costs in the winter on cranking and brake system-related repairs and it always lined up with missing a winter prep. It is very effective in controlling costs.
Homer Hogg, Senior Technical Trainer for TA and Petro, has worked as a truck technician for 30 years. He is ASE-certified, a Daimler Certified Trainer and a member of the Nashville Auto Diesel College Hall of Fame.
Homer Hogg’s “Maintenance Matters” airs on the Dave Nemo Show (Road Dog Trucking, SiriusXM 106), 8 a.m. ET, the first and third Thursday of each month.