Cab-over-engine trucks, also known as low cab forward trucks, give an urban delivery fleet a versatile tool for increasing payload without moving to a higher class because the more compact cab allows a longer cargo box to sit on the chassis.

By locating the driving in a cab mounted above the engine, these trucks also provide greater visibility of objects in front of the truck, which can help when maneuvering in and out of alleys, and making a u-turn on a residential street. Wider wheel cuts enable an impressive turning radius that in some cases can approach 50 degrees.

These benefits were on display with Isuzu's N-Series models, which we drove during about 70 mostly highway miles from the company's Anaheim headquarters heading east to rural Beaumont in Riverside County. We should note that we drove the trucks unloaded.

We drove a three-leg route with the Class 3 NPR, Class 4 NPR-HD, and Class 5 NRR. First some specs. Isuzu's entry-level NPR is the newest model in the N-Series lineup. It's powered by a 3.0L inline-4 turbo-diesel. It has a 20-inch wheelbase and 13,000-GVW chassis with a payload range of 7,435-7,607 pounds.

The NPR-HD is powered by a 6.0L V-8 gasoline engine. Its 16-inch wheelbase and 14,500-GVW enable a payload range of 8,339-8,536 pounds. This truck is the company's highest-volume seller.

The NRR uses a 5.2L inline-4 turbo-diesel to power a truck with a 22-inch wheelbase and 19,500 GVW. Payload ranges from 12,294 to 12,875 pounds.

The trucks deliver power through an Aisin A460 6-speed automatic transmission to rear-wheel drivetrains.

The NPR-HD offered the peppiest ride with its nearly 297 hp, which helped on several roadways with steeper grades. All three trucks provided a stable platform.

A cabover puts the driver in a higher ride position that, when paired with a wider windshield, enables greater visibility of the roadway. Objects would be visible at 8 feet in front of the truck, which gives a driver more time to react, Isuzu told us.

The utilitarian cabins of the trucks serve as a reminder to their essential duty as work tools. Cloth seats, a basic radio, and molded plastic surfaces help keep drivers focused on the job at hand.

The dashboard provides usefull buttons for cargo bay lighting, locking the rear differential (in the NPR), performing a manual regen, getting fuel and diesel fluid levels, and collecting the odometer reading after the truck has been shut off.

Isuzu is expanding its cabover lineup with the F-Series Class 6 cabover that will begin production in the middle of 2017. Until then, its N-Series trucks will continue to serve as core models for a variety of delivery fleets.