Chevron, saying that changing freight patterns have resulted in more severe-duty operation of commercial trucks, has launched a special heavy-duty engine oil to protect engines in these applications while offering fuel economy savings.

Delo 400 SD SAE 15W-30 is an API CJ-4 heavy-duty diesel engine oil. Chevron has formulated it using a new, patent-pending technology to provide benefits specifically for engines with severe-duty cycles.

"The increase in severe-duty operations is due to changing driving habits on highway, including shorter haul lengths, the growth in intermodal delivery, and more stop-and-go operations," said Jim Gambill, Manager Americas Marketing with Chevron Products Company.

The driver shortage means more regional hauls and more slip-seating, he explained. The cost of vehicles continues to go up, so you may have the same truck doing delivery at night but regional on-highway work during the day.

About two years in development, the oil is designed to address the abrupt changes to truck operating conditions experienced in severe-duty cycles, including trucks that are not allowed to idle, trucks subject to stop-and-go traffic or city delivery. It also applies to situations where engine cooling may be stressed by towing heavy loads on steep grades or where cooling performance is compromised.

In stop-and-start operation where the engine is turned off during deliveries, for instance, Chevron-commissioned testing by the Southwest Research Institute showed that due to heat-loading, when the engine was turned back on after 8 minutes, the turbocharger oil temperature spiked by 67 degrees.

"Turbocharger failures are really a significant issue," explained Gambill. Numbers from research firm MacKay and Co. show as many as one in seven trucks will experience a turbocharger failure this year, he said, and turbocharger failures result in $400 million per year in warranty claims – not counting downtime costs.

“In order for engines to last as long as they’re designed to, we need to reassess maintenance practices for this type of operation,” Gambill added. “A critical part of this process is to find an engine oil which is not just heavy-duty, but severe-duty.”

The new oil provides improved oxidation control and deposit control, according to the company. In benchmark testing against competing brands, again done by Southwest Research, the conventional-base 400 SD 15W-30 was statistically superior in oxidation control, including compared to synthetics and semi-synthetics. Testing also indicated excellent high-temperature deposit control.

On top of that, testing showed an 0.7% fuel economy savings compared to a 15W-40 for Class 8 on-highway operations and a 1.9% increase for Class 6 stop-and-start operations – a figure competitive with more expensive synthetic oils, company officials said.

The new oil uses conventional base stocks and features an unusual viscosity rating of 15W-30.

"We saw this need for oxidation resistance and wanted to see if we could do it for a cost much less than synthetics," Gambill said. The new oil is expected to be a little more expensive than an oil such as Delo LE 15W-40, but less than a 10W-30.

Chevron's new oil is made for on- and off-highway applications, including EPA 2010 and tier 4 compliant low emission diesel engines with selective catalytic reduction, diesel particulate filters and exhaust gas recirculation, says Chevron.

It will meet a range of OEM requirements for engine oil, including Kenworth MX, Peterbilt MX, Cummins, Mack and Volvo. It is also recommended for use in select engines from Caterpillar, Daimler, Detroit Diesel and MAN, according to Chevron.

The oil is backwards compatible with previous API oil service categories and engine models where XW-30 oils are appropriate as noted by the OEM.