Second 6x2 Mercedes
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RCEDES-BENZ UK has added a second 6x2 tandem steer, 38 nes gcw tractive unit to its range.
3 Mercedes promised earlier year (CM April 30), its 2028 been joined by the 2025 is less powerful but signiitly lighter, and has wider .1r axle spread to give it a iter gvw under the UK Reguins.
-le 2025 has a 13.9m (12f1 1) outer axle spread and conJently a maximum gvw in UK of 22.36 tonnes (22 tons). isually, 12R-22.5 tyres are
d as standard to the front so that it can be plated at Okg (6.5 tons).
us has been done to allow the high imposed kingpin lings, up to 14,710kg (14.48 ), which the 2025 can take • because the kingpin posion most UK semi-trailers re
e the 2025's fifth wheel to be inted quite far forward. The ommended position is -nrn (321n) ahead of the drive
Much of the weight saving stems from the 2025's lighter chassis frame but its drive axle suspension is also different and lighter than that of the 2028.
Instead of the 2028's air suspension the 2025 has four leaf asymmetric parabolic springs on its drive axle though both models share air bellow suspension for the second steer axle with two leaf parabolic springs for location only. One torque rod is fitted each side to cope with braking torque and the axle has telescopic dampers.
Air pressure to the second axle's bellows is controlled by a load sensing valve fitted to the drive axle.
When this axle's loading reaches 7.4 tonnes (7.3 tons) the valve opens to begin to pressurise the second steered axle's bellows above the normal residual pressure of 1 bar (14.5 psi).
Unlike the 2028, Mercedes' new 6x2 has a load transfer device controlled by a switch in the cab, which can be used to dump all air from the second axle to increase traction. The switch is spring loaded to return to its off position when released in order to prevent possible prolonged overloading of the drive axle.