Not much is known of vehicle making in Glasgow in this period and locomotive-building did not start until 1831 when Murdoch & Aitken of the Hill Street Foundry made the first Scottish-built locomotives for the Monkland & Kirkintilloch Railway. This essay is, therefore based on probabilities, but reasonably secure probabilities.
This period saw a marked increase in road traffic as, with the help of statute-labour, turnpike (or toll) roads, and new bridges were built and city-centre streets were paved. Statute-labour required every able bodied man to provide a number of days free labour a year to repair and build roads and bridges. The increased traffic was largely wheeled, with stage coaches, private coaches and horse-drawn wagons all replacing saddle and pack horses for the transport of people and goods. Some of the new traffic was long-distance, for instance the transport of iron in various forms from Muirkirk in east Ayrshire. Other traffic was short-range, such as the transport of coal from pit or canal basin to consumer.
Because even improved and paved roads were far from perfect the new vehicles must have required constant maintenance and repair. There must have been workshops for vehicle repairs, wheelwrights' shops, and almost certainly coach, carriage and road wagon workshops. The late-18th century wagon ways from the Govan and Knightswood collieries to the Clyde would also have needed wagons and those wagons would have needed regular maintenance, as would the locomotives, carriages and wagons of Glasgow's first public railway, the Garnkirk & Glasgow, which opened in 1830. The latter's carriages and wagons were probably locally made. It is very unlikely that any of these trades were particularly large in scale.