Is Your Truck Ready For Winter Weather ?

October 28, 2020

Uncle Al's Tech Tips of the Week

The information in this tech tip is to educate UTC staff and ensure customer satisfaction and safety.

Winter Weather

Winter preparation is an annual event for fleet and owner-operators from Detroit to Denver — even Tampa can earn big dividends by avoiding unnecessary downtime and safe operation.


Whether you use conventional or extended-drain coolant, your coolant system should get acute attention as sub-freezing temperatures approach. Listed are tips to ensure your system is ready to endure the winter.

  • When implementing preventive maintenance, check the system, especially clamps and hoses, for leaks. As it gets cooler the rubber shrinks and they may start to leak.
  • Check your coolant level often and always use a high-quality coolant ( Brand names products ) and correct type. If not sure reference your factory operator’s manual.
  • Pull a sample of coolant and check the solution to see if the freeze point is appropriate. A 50-50 solution should protect your engine down to -34 degrees F. This can be measured by a handheld refractometer (the most accurate), test strip or hydrometer. This measurement tells you only if the concentration of glycol and water is correct and if the freeze point protection is adequate.
  • Use the test strips designed to test the key inhibitor levels for the coolant you are using to ensure they are preventing aeration, corrosion and cavitation. If in doubt, send a sample to a lab.
  • Do a visual check of the solution in the see-through tank under the hood. It should be clear with bright tint and free of any debris. If milky this indicates immediate attention.


Cold temperatures cause a battery to resist charge, often leaving it at a lower state of charge. If batteries are 3 years old and winter is coming, consider early replacement.

  • During winter routinely check the electrical system, clean the batteries, test and charge them.
  • Checking a battery’s state of charge (SOC) is the best way to determine remaining useful life. There are various system testers that allow you to evaluate batteries, specifically their health and load capabilities.
  • Remember that no-idle systems’ tethered batteries often are discharged to a lower state of charge than starting batteries, which can allow them to be susceptible to damage from freezing or not getting fully charged. A HVAC system producing heat to keep a cab warm requires additional power in watts, so batteries in trucks with no-idle systems typically will encounter reduced service life due to additional discharge demand.


Tires do not demand a lot of extra attention in cold weather, but there are some important things to consider:

  • Maintain proper tire pressure. Since tire pressure drops in cold weather, set the pressure prior to driving when the tires are at ambient temperature. The ideal time to check pressure is during the pre-trip inspection.
  • If the tire is 20 percent below the recommended pressure, it must be considered flat. For safety it should be removed and inspected for damage.
  • If you’re checking air pressure in below-freezing temperatures, it’s possible that moisture in a tire, combined with rushing air, could cause ice to form quickly in a valve core and cause a slow pressure leak. Valve caps help combat this problem.
  • If you routinely drive in areas with severe winter weather, consider tires with a specific tread pattern suited to those conditions.
  • Use tire chains where needed, especially when required by local law. Follow instructions from chain manufacturers and tire makers for proper mounting.
  • Remove chains as soon as they no longer are needed. Chains left on for extended periods will chip, pit and chunk tires, as well as cause road damage.

Air System

Drain out any moisture in your primary and secondary tanks daily

  • Air dryers should be changed out prior to winter to ensure that ice does not cripple the vehicle’s air supply system.


Have the correct oil viscosity for the climate. Check with operator’s manual for cold-weather recommendations.

  • When determining cold-weather viscosity, note that cold-weather oil performance is predicated on ambient air temperatures. Engines are not affected by wind chill values.
  • Do not waste money on cold-weather oil additives. Oil manufacturers blend engine oils for cold-weather performance.


The petroleum industry has created winter blend diesel fuel to prevent waxing or jelling of the engine’s fuel system .

  • For safety and warranty do not play chemist and blend your on fuel concoction.
  • Engine fuel systems are designed and built to operate satisfactorily on fuels and lubricants of good quality marketed by the petroleum industry. Use of any supplementary fuel or lubricant additives is not recommended.
Note: These tech tips are not all inclusive but will help your customer with truck uptime. For more information consult your OEM operator’s manual or your Dealer.

Alan Hertzog

UTO Training Manager

Navistar Inc.-WHQ

2701 Navistar Drive.

Lisle , IL 60532

Cell 484- 788-1809

And More

International Used Truck Centers 41.776180, -88.200918.