Mercedes-Benz Bus History - Daimler

Semitrailer-type buses come in fashion in the 1930s
The LZ 4000, LZ 6000 and LZ 8000 tractor trucks built starting in
1933 were very popular not only for transporting freight, but also
passengers. The advantages of the tractor/semitrailer combination in
freight transportation resulted (and still do today) from the decoupling
of tractor and load-carrying unit. On the one hand, this makes a very
favorable ratio of combination curb weight to payload possible. On the
other hand, the distributing of the load among three axles permitted
advancing into payload regions which had appeared impossible until
then in view of the low weight of the means of transportation itself.
In particular, the tractor/semitrailer combination also cost little in
taxes. To calculate tax, the authorities only included the weight of the
(unladen) semitrailer which rests on the axles of the tractor unit. What
the axles of the semitrailer of the empty combination have to carry is
simply disregarded. On top of that, the tractor/semitrailer
combination permitted dispensing with staff which was absolutely
required for many a drawbar trailer combination: “We should
especially emphasize,” the advertising of that period stated in a
somewhat laconic style “that operation of the tractor is handled by the
driver alone, i.e., ONE-MAN OPERATION.”
To top it all, compared with conventional drawbar trailer combinations
the tractor/semitrailer combination afforded much greater flexibility.
After all, demountable platforms as are common mainly in dual-mode
transport today were not yet a topic in those days. So anyone in those
days who planned his transport operations in the form of a shuttle
service or wanted to make use of different bodies could not get
around the tractor/semitrailer combination: it alone enabled switching
between different body concepts or simply parking the load carrier for
loading or unloading and continuing to make productive use of the
Daimler Communications, 70546 Stuttgart/Germany
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