HELP ! just got a 1997 (p) discovery XS V8i 3947cc for the main purpose of towing my twin axle caravan.I've just been told that some of the older model discoveries need a second cooling system if towing any weight,or it will just knacker the engine the first time I try to tow,because it will overheat.The info was passed on without the person knowing what actual model the disco is.Any help asap would be appreciated. Thanks