FORT WORTH, Texas — The infield lanes of Texas Motor Speedway provided the setting for Peterbilt Motors Co. to introduce members of the media to its new lineup of Classes 5-8 trucks.

PHOENIX — After a model life of nearly 30 years, Kenworth is updating its Class 5 medium-duty vehicles through Class 8, with the introduction of four all-new models: the T180, T280, T380 and T480.

RENTON, Wash. — Kenworth Truck Co. spotlighted the aerodynamic and interior upgrades to its T680 Next Gen Class 8 during a small media event that began at its proving grounds here, then shifted to a 40-mile test drive during which both the day cab and highway models were on hand.

The LED is the alternative to the long-established halogen-enhanced incandescent bulb and the more recent high-intensity discharge (HID) bulbs that have seen some uptake by truck manufacturers.

The American Petroleum Institute’s latest heavy-duty engine oil standards, designated CK-4 and FA-4, have been on the market for more than two years, but only CK-4 lubricants have by and large replaced the previous CJ-4 formulation.

Tire failures remain the No. 1 reason for roadside assistance calls. And most tire-related problems come from underinflation as a result of leaks, punctures or just poor maintenance programs.

Tire wear often is blamed on a number of things, and many times, on the brand of the tire. But aggressive tire wear is a symptom that something else is wrong with a truck.

Not all fleets are convinced of the benefits of air disc brakes. But suppliers maintain there is a growing acceptance of them for heavy-duty trucks, driven by an increase in the deployment of active safety technology, such as collision mitigation and avoidance systems.

When Nikola Motor Co. President Trevor Milton pulled the wraps off the Nikola One prototype Class 8 truck last year and announced it would have a hydrogen fuel-cell power plant, it seemed a radical approach at the time.