Automotive ads often mention terms such as unibody or body-on-frame (BoF) architecture when talking selling points. But what exactly do these terms mean? The former is commonly applied in building passenger cars and crossovers, where the body and chassis of the vehicle are created as a singular unit; the latter, usually seen on trucks and large SUVs, feature the body sitting on top of an underlying frame, as the name suggests.
An overwhelming number of vehicles on the road nowadays are unibody, as this type of construction is usually lighter in weight, more structurally sound and compact in size. The alternative, however, has benefits of a different sort. For instance it’s quite resistant to twisting forces, so traversing rough terrain or towing a lot of cargo is a cinch. In many cases, repairs can also cost less due to multi-component underpinnings that can be isolated and fixed.
In today’s article, we dive into three BoF models, like the time-tested Toyota 4Runner, and why buyers should look into them.
Infiniti QX80 
Measuring 201 inches in length, 80 inches in width, and 75 inches in height, the flagship SUV from Infiniti is no small sight. Highlights include functional athletic body panels contributing to a low 0.367 coefficient of drag, “human-eye” wraparound automatic LED headlights, and a classy and spacious cabin that seats up to eight people.
Only one powertrain is offered: a 5.6-liter V8 producing 400 horsepower, 418 lb-ft of torque, and capable of towing 8,500 pounds. Available in two or four-wheel drive, the QX80 packs some beefy double-wishbone independent suspension utilizing Dual-Flow Path twin-tube dampeners and possessing auto-leveling functionality in the rear.
Toyota 4Runner 
This rugged mid-size utility vehicle was originally launched 35 years ago, and has been the adventuring automobile of choice for countless owners over five generations. Sold in a variety of grades tailored to individual needs — from 2WD to full-time 4WD with a locking center differential and 9.6 inches of ground clearance — all 4Runners pack a 270-horsepower, 4.0-liter V6 engine paired to a five-speed automatic transmission, can seat seven passengers, and haul a maximum of 5,000 pounds.
Ford Expedition 
All new for 2018, the Ford improved on the outgoing product significantly giving the model an aluminum-intensive body atop a redesigned high-strength steel frame that is 300 pounds lighter. For fans of off-roading, an optional FX4 package equips the Expedition with an electronic limited slip differential, specialty shocks, all-terrain tires, seven skid plates, and chrome running boards.
A Terrain Management System has also been introduced, letting users choose one of seven drive modes, each optimizing gearing and throttle and drivetrain response, to suit multiple environments and scenarios. There’s Normal for puttering about town, Sport to increase performance, self-explanatory Tow/Haul (rated at 9,300 pounds), among others. Power is provided by a turbocharged 3.5-liter EcoBoost motor mated to a 10-speed automatic gearbox.