There are an alarming number of reports of cases involving dual cab utility vehicles that have bent their chassis. This can be due to a number of factors, chief among the reports is the fitment of air bags to the rear suspension.
Well, a Google image search of ‘bent dual cab utes’ will reveal several pictures of the phenomenon and I can confirm there is some truth to the myth however all is not as it may seem.
I believe this issue has more to do with overloading the vehicle than it has to do with fitting airbags to the suspension.
Dual cab utes, by their very design, are not as rigid as the equivalent station wagon. Further, compromises have been made in order to accommodate the extended cab as well as maintain a useful tray in the back. This means that there is more of the load placed further behind the rear axle. The towing hitch is also further back than it might otherwise be on a similar station wagon. If too much weight is put towards the rear of the tray and/or on the tow ball, the extra length means extra leverage at the weaker points of the chassis. Take this overloaded combination on off road conditions and a bent chassis is the likely result.
Whether airbags add to this problem is something I am not certain about but given these devices are fitted to enable a vehicle to better carry a load, it wouldn’t surprise me that it is just a coincidence and that the vehicles are being overloaded due to the confidence of having the airbags fitted. Airbags do not increase load capacity.