Sagging springs Triton

As requested by Mitsubishi we took the Triton with the sagging springs to our nearest dealer to have it inspected by a company rep. The dealer service manager told us that the vehicle was within Mitsubishi Aust specs and suggested that we contacted Mitsubishi customer service to lodge our concerns. The dealer also offered to assist us if we wished to repair the rear suspension our own cost. The vehicle was loaded when we took it in and there was no comment regarding the way it was loaded or the load it was carrying, but we never got to meet the Mitsubishi rep. Subsequently I had a phone call from Customer Service at Mitsubishi Adelaide who told me their Regional Service Manager had inspected the vehicle and that his decision was final, which was that the vehicle wasn't designed to carry the loads we carry, and that there was ill distribution of the load. She went on to say that Mitsubishi has appointed a new CEO and that things were tight and that they were not prepared to share some of the cost, as everybody would want them to do the same for them. I told her that we had purchased the vehicles in good faith from a dealer who was told what we wanted to carry and the type of work the vehicle would be doing. I asked what would happen to our vehicle warranty if we fitted aftermarket springs, and she said it would not affect the overall vehicle warranty, only the springs. We plane to pursue this issue and will keep the pressure on from our end.