1931 to 1939 The company was established on 1 April 1931 as
Oy Suomen Autoteollisuus Ab (SAT). It originated from two neighbouring Helsinki-based automobile coach builders,
Autokoritehdas and
Autoteollisuus-Bilindustri, both of which had fallen into financial troubles by the beginning of the 1930s. The banks, which were funding both companies, pressed them to put together their operations under one company. The founders were Emil Anton Winckelmann,
Lars Wilhelm Åberg and Karl Arthur Nordgren. In the first company meeting the company general manager was selected John Hellsten and the technical manager was appointed
Tor Nessling. At first SAT continued the coachbuilding business which it had inherited from its predecessors, but also put into practice the plan of building own vehicles, which was evolved already earlier, when Autoteollisuus-Bilindustri had ordered few
Volvo chassis for outfitting. These chassis formed the basis for the first pre-series of vehicles. As many people had suggested the successful name, the winner of the 1,000-mark prize was selected by lotteryhe was young Veikko Arohonka, actually signed up by his older brother Eino, who later became a writer. from 1932 The first nine Sisus, models
S-321 and S-323, were handed over to the customers in 1932. Six of them were lorries and one was a bus. The first production series, based heavily on Volvo components, were made in 1933. Beginning of domestic vehicle production led to an odd episodethe Finnish government became concerned about losing toll incomes because of the locally built vehicles. In 1933 Dr. Juho Jännes was assigned to investigate the financial impact of domestically produced automobiles. The outcome was that if 500 of the vehicles annually sold in Finland were produced domestically, the state would lose 700,000 marks because of reduced toll income but the benefit due to employment effect would be between 17–27 million marks. John Hellsten was replaced by Tor Nessling as general manager in 1932. Nessling started to develop the business determinedly; the technical challenges caused by weak locally produced parts were resolved by time and the degree of domestic work could be increased. Another, persistent problem was the continuous lack of cash reserves. Nessling tried to lobby the government underlining the positive effect of domestic vehicle production, but he was not listened, and the state reduced the tolls of imported vehicles making competition more intense. The company owners did not believe in the potential of domestic vehicle industry and Nessling could obtain a large part of the shares from the funding banks for relatively cheap, eventually owning 80% of SAT. The continuous pressure and repeating setbacks did not discourage the personnel and management, who did what ever it took to solve out the challenges. Over time the technical quality was reached to a such level that SAT could convince the customers that the relatively high price of Sisus, compared to imported vehicles, pays off due to their robustness. with which SB-series was produced in parallel 1938–1941. The first three-axle lorry was produced in 1935. Right after the Winter War in spring 1940 SAT started producing an own
carburettor type under name
Häkä for
carbon monoxide fuel. Technically the carburettor was not one of the most successful of its kind. The development work was continued with
subsidies of the state until it was finally filed in 1946 as unnecessary due to improved availability of
petrol. SAT started own engine production in 1940 under
Hercules licence. This together with
tram building and 1942 started axle production led to lack of space in the factory area. The first plans of moving some of the production out from Helsinki were made already before the war. In 1942 the construction of new premises began in
Karis, which was out but sufficiently reachable from Helsinki. Coach- and cabin building was transferred first, after which the tram production followed; building of lorries stayed exclusively in Helsinki until 1950.
Yhteissisu made by
Yhteissisu At the same time when SAT built the new factory in Karis, the
Finnish Defence Forces reported needing thousands of vehicles in the near future. SAT suggested building the factory larger in order to meet the demand. However, the importers of other makes as well as some politicians suspected that SAT tried to use the war to gain a dominant position in the Finnish market.
Vanaja municipality next to
Hämeenlinna was selected for the factory location. The war was over before Yhteissisu could start serial production at the full scale. Yhteissisu had the right to use the Sisu-brand until June 1948. When this expired, the company was renamed
Vanajan Autotehdas (VAT) and its products were named Vanaja. VAT became a strong competitor to SAT in the Finnish market which was small but still protected by import restrictions. According to the contract with Yhteissisu, SAT was not allowed to produce lorries during the five years' period. SAT made Sisu S-15 buses but some of the chassis were fitted with
lorry cabins and superstructures. The first heavy forward control lorries were the 1956 produced
B-56 and 1958 introduced
B-72, both of them being built on bus chassis. The small forward control lorry
Nalle-Sisu KB-24 came to market in 1955. Other notable models introduced in the 1950s are the heavy dumper trucks
K-36, the first 6×4 driven Sisu,
K-32, and
K-44 with a North European specialty, 4×4+2 layout. SAT started partnership with
Leyland Motors Ltd. in 1950. The background originates to friendship between the general managers of both companies, Tor Nessling and
Donald Stokes. For a while the SAT test department investigated for possibilities of producing Leyland engines under licence; trials for better output and torque were made on test bench with
turbocharged applications, before Leyland even had taken such into production. As a part of the partnership SAT became representative of Leyland products in Finland. The 1954–1959 produced trams equipped with two-axle bogies featured progressive steel structure technology that
Valmet and
Tampella later copied for their jointly developed tram type. SAT produced
4×4-driven "rail trucks" for railway maintenance work under assignment of the
Finnish State Railways in the 1950s. The first ones, JXB 7, JXB 12 and JXB 13 were equipped with a one-man cabin; later came JA-4 and JA-5 with cabins for three. The mechanical crane was replaced by a hydraulic one in the 1966–1972 produced JA-9SV, JA-12, JA-14 and JA-16. From 1958 SAT produced rail control vehicles which were equipped with coachwork similar to forward control buses. Some of them were produced jointly with and
VAT. Also some
KB-48 4×4
road-rail lorries were delivered. Altogether SAT delivered 150 rail trucks of various types to the State Railways. In 1963–1970 SAT produced three types of two-axle light
diesel locomotives. The Sisu JA-7 were powered by Leyland diesels and the railway company used designations Tka 2 and Tka 3. In 1951 and 1955–1957 SAT imported total 105
Trojan vans. The first imported vehicles undertook many changes before they met the requirements. Some of them got a Finnish made body. In 1956 SAT built a series of ten
DKW Schnellasters from
CKD kits imported from
West Germany; they were sold with name
Donau-Sisu. Additionally, some modifications were made for SAT-imported
Aveling-Barford and Avelin Austin graders and dumper trucks and also
Leyland Terrier and
BMC Mastiff lorries. SAT had plans of starting local production in
Medellín jointly with Leyland Motors but the project was eventually cancelled due to financial risks. In the early 1970s the
Andean Community of Nations decided about starting its own lorry production and the successful trading came to end after about 1200 sold units. In 1961 SAT produced the ballast tractor
K-50SS which is still the largest automobile ever built in Nordic countries. The first European serial built lorry with a hydraulically tiltable forward control cabin,
Sisu KB-112, was introduced in 1962. The 1965 introduced
Sisu K-148 featured bonnet and wings produced from reinforced plastic. Due to lower costs and better durability the solution was soon applied on the whole conventional cabin model range. During the 1960s SAT made a number of innovations, experiments and extended to new areas. In 1961 the radial type hydraulic motor
Sisu Nemo was patented. The main use was powering of
trailer axles but Nemos were installed also in number of other applications. The 1963 introduced K-138 features another innovation of the same period: vertical ejector exhaust pipe that dilutes exhaust gases. At the early 1960s also wide tyres to substitute double wheels were tested; the experiment done together with
Nokia did not, however lead to production. In 1964 Leyland Motors became minority owner of SAT. The other owners were Tor and his wife Maj Nessling, and Arne Söderberg. General Manager Tor Nessling resigned in 1970, after leading the company for nearly four decades. He was replaced by
Erik Gillberg. Before that, the state had become an owner of the company in the VAT merger first with 17.2 percent share. The state grew its share in the company gradually. In 1976 the state signed the so-called tripartite agreement with
British Leyland International and
Saab-Scania, which both held 10% share of SAT thereafter. General Manager Gillberg led SAT through an extensive renewal of the whole product range. The Sisu S-series lorries were a result of this; the first example, light forward control
SK 150 was introduced in 1980. The development programme had, however, demanded excessive amount of money and the company main owner, the state, removed Gillberg from office at end of 1983. He was replaced by
Jorma S. Jerkku who immediately started a heavy reorganisation programme. The company management was cut smaller and moved from Fleminginkatu to
Konala in 1985. After some other functions were moved to Karis and Hämeenlinna, the Fleminginkatu premises were sold. Car sales, as well as
Iveco representation were discontinued at the end of 1988. In the same year the plastics factory in
Mäntyharju was separated under name Simex Oy and sold. Although Jerkku's actions were shocking to many, he by all odds stabilised the company.
1994 to 2003: Merger and break-up In 1993 Jorma S. Jerkku was replaced by the company Vice President
Heikki Luostarinen. Already year after that he was followed by . A period of turmoil started: in April 1994 Sisu-Auto bought from Valmet its Transmec unit and
tractor production; as a consequence, Valmet became minority owner in Sisu-Auto with 24.13% share. As also Valmet was state-owned, the state of Finland owned directly and indirectly total 99.01% part of Sisu-Auto. The new company name was
Oy Sisu Ab and its business units were Sisu Tractors with 48% share,
Sisu Terminal Systems (19%), Sisu Logging (12%), Sisu Trucks (10%), Sisu Defence (4%), Sisu Factory Automation (4%) and Sisu Components (3%). Subsequently, the corporation was subdivided; first Oy Sisu Trucks Ab in November 1994 and at the beginning of the following year Sisu Defence Oy, Sisu Terminal Systems Oy and Fastems Oy; additionally, Sisu Diesel Oy was separated from Sisu Traktorit Oy. In 1995 Fastems was sold to Mercantile. The Hämeenlinna axle factory became Sisu Axles Oy at the end of the year. Sinex was sold in 1996. In January 1997 the company main owner, the state, agreed about selling main part of Sisu corporation to Partek. This was carried out by gradual shift of the ownership during the year. In the meantime, the state continued the restructuring: Germany based Stama Maschinenbau GmbH was sold to Chiron-Werke GmbH & Co. KG. Sisu Defence went to the state, which later joined it to new defence industry company
Patria. was finally replaced by the new E-series launched in 1996. In 1997 Sisu Auto signed an agreement of extensive co-operation with
Renault V.I.; Sisu started using Renault components and represent Renault in Finland. Consequently, the new cabin model was replaced by such of Renault just one year after its introduction. mobile crane with Mercedes-Benz cabin
2004 until present: New ownership In 2004 a group of Finnish investors became owners of Sisu Auto, while Kone remained a minor owner with under 20% share. General Manager
Nils Hagman, who had replaced Ojanen in 2001, left his position for
Teppo Raitis in 2004. Raitis focussed the product scope on customised heavy duty multi axle vehicles for
niche markets. Raitis was replaced by
Olof Elenius in 2007 In the same year Sisu Auto had sold its aftermarket services to Veho, which also represents Mercedes-Benz. Also the sales of civil lorries were moved to Veho in 2010. The component partnership with Renault was ended in the same year; Sisu introduced the
Polar series which uses components of Mercedes Benz. The first armoured
8×8-driven Sisu E13TP military vehicles were produced in 2008. Between 2009 and 2012 the Sisu production was operated by
contract manufacturer . Elenius bought the Sisu Auto shares jointly with the Deputy General Manager Timo Korhonen in 2010. In 2013 Olof Elenius left his position and sold his share to Timo Korhonen, who now became the general manager and the sole owner of the company.
Bus coach and chassis production The first Sisu bus was produced in 1932 as a part of a pre-series of the first model. Also the coaches were produced by SAT. After merger with VAT in 1968 Sisu bus chassis production was moved gradually from Karis to Hämeenlinna. In the 1970s Sisu chassis with Lahti bodies In the late 1970s SAT produced jointly a hybrid bus prototype
SWS for
Helsinki City Transport together with Wiima and
Strömberg. The very last Sisu buses were produced in Hämeenlinna in 1989, equipped with Ajokki coaches and delivered to a Soviet customer.
AEG and
ASEA produced models sold to Helsinki in the 1920s and early 1930s was evident. Later the tram production was separated to a new SAT owned company
OY Karia AB. During the Second World War lorry production was transferred to another company,
Yhteissisu, which was set up to produce lorries and buses for the military. In 1959 SAT introduced Kärppä-Sisu K-35 for military use but 4×2-driven. Production of military off-road vehicles started in 1964 when SAT presented
KB-45, a new light
4×4 lorry. The military vehicle production was moved from Karis to Hämeenlinna when the upgraded
A-45 was presented. Medium heavy
SA-150 and heavy
6×6-driven
SA-240 production followed after.
SA-110 was a light lorry prototype which was only produced six units. In 1990 the demining vehicle
RA-140 was introduced and they were produced a small series starting from 1994. The best known Sisu military vehicle is the armoured personnel carrier
Pasi in different variants. The production of the first model, XA-180 was started in 1984 after thoroughgoing testing. Pasis have been commonly used in UN peacekeeping missions. The last Sisu-produced variant is XA-186, the later models have been produced by
Patria when Sisu Defence was sold to the state. The last Pasis were produced in 2005.
Mobile crane chassis VAT had started producing mobile crane chassis for
Lokomo in 1968 and SAT continued the business after taking over VAT. The types were 6×4 driven T-103, which was sold as Lokomo A330/331 NS, and 8×4-driven T-108 and T-109, of which Lokomo models were A 350/351 NS and A 390/391 NS. Making of mobile crane chassis was discontinued in 1981. The production in Hämeenlinna factory totalled 542 units.
Vehicle imports SAT planned starting vehicle imports in the late 1930s; a number of British car makes were considered, including
Morris Motors products, as well as American tractors. One
Austrian
Steyr Typ 220 Innenlenker visited in Finland for display in early 1939. The import business started, however, shortly after the Second World War. In 1946 SAT became representative of
Rolls-Royce cars and engines,
Rover and
Bentley followed in 1948. At the same time also West German products came to selection, for example
Auto-Union cars and motor cycles and König outboard engines.
Key components Engines The first Sisus were powered by Volvo supplied
Penta engines. The 1934 presented Sisu SO-models were equipped with Finnish produced Olympia engines which turned out to be too weak and unreliable. Therefore, the power source was changed again already in 1935 launched SH-series which was powered by American
Hercules engines. Henschel was finally dropped off from the selection because the weakening Finnish mark in relation to German mark made them too expensive. The first Sisu with British made Leyland engine came already in 1948. From the early 1950s Leyland was virtually the standard power source in Sisus for during the following three decades; about 30 different types were in use. Some of the types were very robust but also technically failed units appeared with repeating problems; the Leyland O.801 V8 diesel is particularly mentioned as one of the worst. In 1997 Renault started a component supply partnership with Sisu. In parallel with Renault Engines, American
Mack came to the selection. The 2002 introduced Sisu with 630-hp
Caterpillar C-18 engine raised Sisu to new level of power. For a while Sisu had in its selection most powerful serial produced lorry of Europe.
Valmet engines were used occasionally in various Sisu models since 1969. The first version was a four-cylinder type 411 available for Kontio-Sisu LP-138. Later a horizontally mounted 611 was used to power the modular chassis SB-127 "Moni-Sisu" designated for buses and special vehicles. Also some 1980s produced S-type Sisus used Valmet. Valmet was the dominant engine in military vehicles during the 1980s. They were dropped off from selection in the 1990s because the engines were not powerful enough and did not fulfill the emission regulations for on-road use. Petrol engines came back into use in
NA-110GT which uses GM V8 engine, and NA-140BT with
Rover V8. During the Second World War produced Sisu S-21 featured
ZF gearboxes, which were later, in the Yhteissisu produced units, substituted by domestically produced
Rosenlew products.
Axles . The axles used in early Sisu models were produced by
Timken. Later the axle housings were locally produced. Soon after Vanajan Autotehdas was merged into SAT in 1968, During the Renault partnership also Renault axles were in selection.
Cabins , introduced in 1962, was the first serial produced European lorry with a hydraulically tiltable cabin. The very first Sisu
cabins were self-produced with vertical windscreen but later they were reshaped to a more sleek appearance. External producers were used already since end of the 1930s. The common practice was that the customer selected the cabin supplier. Some of the cabin suppliers were
Auto-Heinonen,
Messukylän Autokoritehdas,
Valmet, Tampella, Ajokki, Lahden Autokori,
Kar-Pe,
Linjakori and – the last one was the most significant supplier during the 1950s and 1960s. Also the SAT-owned Karia was a significant supplier. Some Jyry-Sisus sold in Sweden were equipped with locally produced cabins. Until the 1950s the cabins had typically a wooden frame. The first completely steel structured cabin came in 1955 introduced Sisu KB-24. The structure was soon adopted also in other Sisu models. The diversity of cabins was narrowed down at the early 1960 when structurally integrated cabins became more common. A typical example is
KB-112/117 with a tiltable cabin. In 1965 K-148, the first Sisu with a plastic bonnet, was introduced. Soon plastic became used also in front wings as well as forward control cabin internal engine covers and dashboards. KB-45 got a plastic roof and back wall. SAT opened a new facility in
Mäntyharju for plastic part production; parts were made also for Scania and bus coach builders. L-model buses can be distinguished by two-digit model series codes; later L made a return to Sisu model names in lorries, but with three-digit model numbers. Since 1970 the engine configuration of bus chassis was indicated with a second letter: BE meant front engined, BK middle engined and BT rear engined chassis. Conventional cabin lorries were K, U, UM, UP, L, LP, LM, LV and R. Lorries with forward control cabin were KB, M, MS, A, AH, AS, MA, MI and MK.
Terminal tractor and
mobile crane chassis models started with letter T. The model code was followed by an engine type code, consisting two or three letters. A short-lived trade name was 1966 introduced Ukko-Kontio, "Mighty Bear", that fell in its size between Kontio and Jyry.
Model codes 1977–1996 A new model code system was taken to use gradually starting from 1977, of which high variant was SM. SC was an especially low model. The conventional cabin models were low SL and SN and the high SR. There was also the option of an aerodynamic version of the S-series, called the Futura, which debuted at the Moscow Auto Show (MIMS) in August 1993. The number was not a running model number any more, but indicated the engine output in kilowatts. Also application specific trade names were taken to use: logging vehicle became Sisu Timber, earthmover Sisu Rock, hook loader Sisu Roll, road maintenance vehicle was named Sisu Works, mobile crane Sisu Crane respectively and wheeled vehicle transporter Sisu Carrier. The 2010 introduced model with Mercedes-Benz components got the trade name Polar. The early model names are DK12M and DK16M; the K stands for high cabin, the number for engine displacement in litres and M means that the cabin is forward control type. The application specific model names are still used in parallel. In 2014 the company introduced new models, model names CK and CM while the commercial name for these products continues as Polar. == Models ==