Nissan X-TRAIL Gearbox & Transmission Problems

It depends on the weight you're going to tow and the terrain you'll be traveling over. Your caravan is well within the X- Trail's weight limits, but remember the weight the fully loaded weight, not just the weight of the caravan. If the caravan weighs 1300 kg fully loaded, and if the roads you will be traveling on are relatively flat then you should be able to get away without a cooler. But a cooler is good insurance against overheating the transmission, and overheating it is a good way to kill it.

Although you appear to be well within the towing capacity of the X-Trail it's wise to fit an external cooler. Overheating an auto-transmission is like a death sentence to it.