We are at present running an 'x' reg td5 as a mountain rescue vehicle. on a recent outing we lost all the coolant on our way back to base and had to be recovered. upon looking at the vehicle our repairer tells us that it will need a NEW radiator because the original has been damaged beyond repair, I am told that it is on the face of the radiator that the damage has occured, and yet there has been no impact to the front grill etc so I don't see how this could have happened. Is this a common problem if so how do we guard against it happening again ?