Lots of jeep action. They drive the jeeps pretty hear near the end. At about the 8:30 mark there some hard driving video. The jeeps were bouncing pretty hard!

From archive.org: “Not the greatest film quality. National Archives description: “A 4.2″ mortar fires high explosive and phosphorus shells which explode on targets. Transportation of mortar and ammunition in large truck (10 men-10 rounds) is compared with that of a jeep towing a trailer bearing a mortar and ammunition (2 jeeps-6 men-48 rounds). Jeep and trailer units are tested at various speeds and on all types of terrain, fire mortars from barge landing craft as an island is approached, drive off barge, and are freed from ditches and other obstacles by their crews.”
National Archives Identifier: 24456”