In this weeks commercial motor there is an article about the new Volvo eight wheelers and how they intend to make them lighter.
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The most surprising development concerns 6x2 and 8x2 mixer chassis. Before you think the Swedes have lost the plot,they reckon that 80% of mixers could cope without a fully driven bogie.The trailing rear axle could be lifted and/or steered and the combination of diff lock and a lifted axle carrying fifteen tonnes of load at low speed should give adequate traction.
However once again the big selling point is weight:with an Italian CIFAmixer body,Volvo claims a full 8m3,19 tonne payload is a reality on the eight legger which is better than any 8x4. With full air suspension it is claimed to cope more effectively with mixer drum torque loadings as well as saving 550kg compared with the conventional B ride rear bogie suspension.
quote.
I have lost count of the amount of 6x2 and 8x2 block wagons I have seen stuck !!! What about when you have to go up a steep climb in reverse and the first drive axle clears the ground?
Fifteen tonne on one axle of soft uneven ground 
If you want to run an eight wheeler mixer Foden will sell you one with double drive, so will Iveco and Seddon Atkinson.
The Foden and the Atki both do come in under the weight I cannot find another that will,although I have not tried the Iveco.
Just thought I would give you some food for thought be very carefull if you go down the eight wheeler route.
cheers
STEVE.
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