In the years before mass media, the best way to get information to a large number of people was to physically visit them. Arguably, one of the most extensive concerted efforts in this regard was GM's Parade of Progress, which campaigned specially built mobile displays traveling the highways and byways of the U.S. in search of an audience.

Eight unique vehicles were created to accomplish this mission. The first of these, in 1936, resembled converted GM moving vans, but in 1939, more representative messengers of the future were designed; vehicles not only transporting advanced ideas, but were themselves representative of them.

Twelve massive Futurliners were constructed at GM's Yellow Coach bus facility before heading to Fisher Body for final modifications. Power was provided by a four-cylinder diesel pushing through a four-speed manual transmission. Two 45-gal fuel tanks kept each fed. The wheelbase accounted for 248 in. of the overall 33-ft length. Width was 8 ft. While the numbers are similar to the GM passenger-bus dimensions of the time, most other features were quite unique.

Mechanically, the side-by-side front tires were the most unusual feature. A power-steering unit was required to facilitate steering under slow-speed conditions (reliability of these units was questionable in the rigors of the multi-state trek). In addition, each wheel had its own brake drum. The sheer mass of the Futurliner could overpower the brake technology and, at least once, resulted in unwanted contact between two Futurliners.

In most examples, the slab-sided body opened in a clamshell arrangement to reveal exhibits within. A lightbar housed within the roof could be raised several feet to provide area lighting. An onboard diesel generator supplied the power necessary for the caravan. The futuristic bubble-top canopy over the driver's area created a detrimental greenhouse effect inside the Futurliner that overheated the driver and passengers.

WWII forced the Futurliners into mothballs. They wouldn't be resurrected until 1953. Upgrades included air-conditioning and a cabin redesign extending the sheetmetal forward to shield the cockpit. Other improvements were a new drivetrain featuring GM's gutsy 302 inline-six-cylinder gasoline engine. The manual trans gave way to a four-speed automatic. Despite the new technology, top speed remained in the 40-mph range.

The Parade of Progress would campaign for three more years before disbanding in 1956 due to lack of interest. Futurliners that weren't sold or donated were left to rot. Several, however, are currently roadworthy in various states of originality, while others are undergoing restoration.

For more information about Futurliners, contact the National Automotive & Truck Museum, 100 Gordon, Auburn, Indiana 46706-0686; 219/925-4560; www.natmus.org.