Diesel vehicles are the mainstay of most fleets, trusted for their hardworking reliability and toughness under even adverse conditions. But these workhorses need specialized care. Diesel engines operate under a lot more pressure than standard engines and need regular preventive maintenance to make sure they continue to perform at their best.

The EPA is also interested in making sure your diesel vehicles are well maintained in order to reach the lowest level of emissions and achieve the best fuel economy possible.

Here are some recommended practices for effective diesel vehicle maintenance:

  • Replace intake air filters — Diesel engines use a lot of air, so it’s vital that the air filters are working as effectively as possible.
  • Monitor fuel and oil consumption — Engines with high fuel or oil consumption may need to be repaired.
  • Repair any exhaust leaks — Exhaust leaks increase vehicle emissions, and create dangerous conditions if lethal carbon monoxide gas makes its way into the truck cab. Inspect exhaust systems regularly, and make repairs as quickly as possible.
  • Avoid excessive idling — Excessive idling can cause the cylinder block to become scored. This is especially a problem in the winter when truck drivers may keep the engine idling for hours on end to keep the cab warm at night. When an engine is idled continuously, especially in cold weather, a lack of lubrication can lead to the piston scoring the cylinder block. It is better to switch the engine off and instead use a coolant heater to maintain warmth. Idle times can be monitored using Telogis Fleet.
  • Beware of using fuel additives — Fuel additives may impact engine and emission control system durability. A list of registered additives can be found on the EPA website. This list simply provides information about the content of the additive, and isn’t to be viewed as an endorsement from the EPA. In fact, it is no longer necessary for fleet drivers to add fuel lubricity additives to highway diesel fuel.
  • Keep engine profile information — When fleet vehicles are evaluated for retrofitting, make sure you keep the results of those tests (i.e., exhaust temperature data) for future reference.
  • Monitor engines and fuel systems for leaks — Before you install new parts or switch fuel types, make sure you inspect the engine and fuel. Fix any fuel or oil leaks before making changes or repairs.

Cleaner burning diesel

One aspect of running a well-maintained diesel fleet is to run vehicles on ULSD (Ultra Low Sulfur Diesel) when possible. In fact, ULSD will be the only diesel available after December 2010, so fleets not running their vehicles on it will need to make some adjustments.

ULSD has definite benefits for the environment as well, contributing to an improved air quality, which reduces the risk of respiratory diseases, particularly in young children and the elderly.

If you have questions about running ULSD, visit the website for some common questions and answers about using the fuel.

Regular maintenance means having an early warning system

Looking after your diesel vehicles is all part of an ongoing fleet maintenance program. Regular fleet maintenance is also critical for keeping your fleet safe and minimizing breakdowns and unnecessary repairs.

The key to a good maintenance program is making repairs early and receiving advance notice of upcoming vehicle maintenance. Fleet management software can do this automatically by tracking a vehicle’s mileage or engine hours, and sending you an alert when there an upcoming service is due.

Find out more about how an effective preventive maintenance program can improve fleet safety and reliability.