Caterpillar CT680

The CT680 used a set-forward steer axle and, with a 124-inch bumper-to-back-of-cab hood, was the longest of Caterpillar's three short-lived truck models, with its CT13 diesel rated 410 to 475 hp and 1,450 to 1,700 lb-ft for heavy vocational work. Shown in long-hood form in 2015 with a 15-liter engine promised to follow, the bigger diesel never materialized: Caterpillar abruptly killed the CT660, CT680 and CT681 and exited the on-highway truck business in early 2016, less than a year after deciding to design and build its own trucks in-house.