Land Rover entered production in 1948 with what was later termed the Series I. This was launched at the Amsterdam Motor Show. It was originally designed for farm and light industrial use, and had a steel box-section chassis, and an aluminum body.
Originally based on the US Army Jeep the Land Rover was a single model offering, which from 1948 until 1951 used an 80 in (2032 mm) wheelbase and a 1.6-litre petrol engine. This was a basic vehicle, tops for the doors and a roof (canvas or metal) were optional extras. In 1950, the lights moved from a position behind the grille to protruding through the grille.
From the beginning it was realised that some buyers would want a Land Rover's abilities without the spartan interiors. In 1949 Land Rover launched a second body option called the "Station Wagon", fitted with a body built by Tickford, a coachbuilder known for their work with Rolls-Royce and Lagonda. The bodywork was wooden-framed and had seating for seven people. Tickfords were well equipped in comparison with the standard Land Rover, having leather seats, a heater, a one-piece laminated windscreen, a tin-plate spare wheel cover, some interior trim and other options. The wooden construction made them expensive to build and tax laws made this worse — unlike the original Land Rover, the Tickford was taxed as a private car, which attracted high levels of Purchase Tax. As a result, less than 700 Tickfords were sold, and all but 50 were exported. Today these early Station Wagons are highly sought after. There are less than 10 still known to exist, mainly in museums, and they can change hands for as much as £15,000.
In 1952 and 1953 the petrol engine was replaced with a larger 2.0-litre unit. This engine was "siamese bore", meaning that there were no water passages between the pistons. Around this time the Land Rover's legal status was also clarified. As mentioned above, the Land Rover was originally classed as a commercial vehicle, meaning it was free from Purchase Tax. However, this also meant it was limited to a speed of 30 mph on British roads. After an appeal to the Law Lords after an owner was charged with exceeding this limit, the Land Rover was classified as a "multi-purpose vehicle" which was only to be classed as a commercial vehicle if used for commercial purposes. This still applies today, with Land Rovers being registered as commercial vehicles being restricted to a maximum speed of 60 mph (as opposed to the maximum 70 mph for normal cars) in Britain, although this rule is not often upheld nowadays.
1954 saw a big change: the 80 in (2032 mm) was replaced by an 86 in (2184 mm), and a 107 in (2718 mm) "Pick Up" version was introduced. The extra wheelbase was added behind the cab area to provide additional load space.
1956 saw the introduction of the first five-door model, on the 107 in chassis known as the "Station Wagon" with seating for up to ten people. The 86 in model was a three-door seven-seater. The new Station Wagons were very different to the previous Tickford model, being built with simple metal panels and bolt-together construction instead of the complex wooden structure of the older Station Wagon. They were intended to be used both as commercial vehicles as people-carriers for transporting workmen to remote locations, as well as by private users. Like the Tickford version, they came with basic interior trim and equipment such as roof vents and interior lights.
The Station Wagons saw the first expansion of the Land Rover range. Station Wagons were fitted with a "Safari Roof" which consisted of a second roof skin fitted on top of the vehicle. This kept the interior cool in hot weather and reduced condensation in cold weather. Vents fitted in the roof allowed added ventilation to the interior. While they were based on the same chassis and drivetrains as the standard vehicles, Station Wagons carried different chassis numbers, special badging, and were advertised in separate brochures. Unlike the original Station Wagon, the new in-house versions were highly popular.
Wheelbases were extended by 2 in to 88 in (2235 mm) and 109 in (2769 mm) to accommodate the new diesel engine, to be an option the following year. This change was made to all models with the exception of the 107 Station Wagon, which would never be fitted with a diesel engine, and would eventually be the last series I in production.
Finally, in 1957, the "spread bore" petrol engine was introduced, followed shortly by a brand new 2.0-litre Diesel engine that, despite the similar capacity, was not related to the petrol engines used. The petrol engines of the time used the rather out-dated inlet-over-exhaust valve arrangement; the diesel used the more modern overhead layout. This diesel engine was one of the first high-speed diesels developed for road use, producing 52 hp at 4000 rpm.
This engine was slightly longer than the original chassis allowed, so the wheelbase was increased from 86 to 88 in (2235 mm) for the short-wheelbase models, and from 107 to 109 in on the long-wheelbases. The extra two inches were added in front of the bulkhead to accommodate the new diesel engine. These dimensions were to be used on all Land Rovers for the next 25 years.