DAILY MCA2014 4x4 ‒ BODYBUILDER INSTRUCTIONS
APPLICATIONS OF SUPERSTRUCTURES
3.3 CONNECTION BETWEEN CHASSIS AND COUNTER CHASSIS
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– Printed 603.95.994 – 1 Ed. - Base 05/2015
Connections with greater elasticity
When the connection needs greater flexibility (e.g. vehicles with high stiffness of the superstructure such as vans, tanks, etc., used
on winding roads or in poor conditions, vehicles for special use, etc.), hardware similar to the type indicated in Figure 9 should be
adopted in the area behind the driver's cab.Brackets accompanied by rubber plugs (1) or coil springs (2) should be used.
193872a
Figure 9
1. Rubber block 2. Coil spring
Bear closely in mind that:
● the elastic element characteristics should be suited to the stiffness of the superstructure, the wheelbase and the type vehicle
use (irregular road conditions);
● stiffness must progressively increase for fixing points closer to the rear part of the chassis;
● the overall connection capacity must also include fixing points resistant to shear stress to be positioned near the rear suspen-
sion.
Consequently, the first fixing behind the cab must be made using one of the solutions shown in Figure 9; especially when the vehicle
has a long wheelbase, this solution must also be replicated for the next fixing, modifying only the stiffness.
For example, in the case of brackets with rubber pads, elements must be used having the same hardness (sh = 83), assembled in
dual pairs for the first bracket and single pairs for the next bracket, with M10 screws and tightening torques of di 15-18 Nm.
Also bear in mind that:
● for rubber plugs, use materials that ensure good elasticity over time.
● every solution requires the preparation of appropriate instructions for interval controls and possible resetting of the tightening
torques of parts.
● In versions where the vehicle is lifted by hydraulic stabilisers (e.g. cranes, aerial work platforms), limit the collapse of the elastic
element to ensure sufficient cooperation of the counter chassis and avoid excessive bending moments on the original chassis.
Also bear in mind that:
1. in the case of superstructures that generate high bending and twisting moments (e.g. a crane behind the cab), the counter
chassis must be properly sized to support them;
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