A further development of the LP forward control series was presented in 1958 as the 3-axle LP 333. The new model's introduction coincided with the German "Seebohm" regulations which significantly restricted weight and length measurements. The LP 333 was designed to maximise payload capability under these new laws, and utilised the cab over engine design which until the mid-1950s Mercedes had been sceptical of. The new model led to a sudden increase in popularity of forward control trucks in Germany after the restrictive regulations were introduced.
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A restored LP 333 example |
The maximum gross combination weight under the new regulations was decreased from 40 to 24 tonnes, and the LP 333 offered a payload capacity of 9.1 tonnes. The reason the Mercedes designers had chosen this axle layout was because an exception in the law meant that a three axle truck was permitted to pull a 16-tonne heavy-duty trailer. The engineers chose to place an extra axle at the front of the vehicle instead of the rear due to technical issues caused by the new length restrictions. This meant that coupled to a 16-tonne trailer the LP 333 offered a payload of 20 tonnes and a maximum combination weight of 32 tonnes, and thanks to a loophole in the restrictions this was deemed legal.
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LPS 333 articulated tractor-trailer |