What is technically the difference of 2.5/2.6 or 3.2/2.6 as both 2.5 and 3.2 have higher allowable mass of a mobile home with brakes (left column), brakes might be same and 2.6 has more power than 2.5. Difficult to understand. Would like to increase in my 2.6 it to 1850kg.

Assuming that the OP was hoping to tow a larger caravan I would personally stick with the kerb weight figures as mentioned previously.
The maximum towing weights shown above for trailers are derived from the vehicles ability to pull away from a dead start on an incline, of a gradient of which I can't remember offhand.

As GrahamK stated, different models have different maximum towing weights, even though the vehicle may weigh potentially the same.
So, a 3.2 Omega gets a higher maximum towing weight than the smaller V6's purely because it is more capable of hauling arse from a standstill on a gradient. Outfit stability obviously comes in to it so they set that figure according. I'm surprised that the 3.0/3.2 aren't paired but then the 3.2 is far superior.

So, in reality, the 2.5/2.6 may be as stable on the flat as a 3.2 but the 3.2 gets the higher maximum towing figure based on its gradient start from standstill when towing.

Hope that helps to explain the difference in figures.

Incidentally, I was following a Landcruiser Amazon a few years back when all of a sudden his twin axle decided to give it a savage arse kicking (tail wagging the dog). He was lucky, as was I when it happened to me, so it pays not to become too complacent. It's an experience that I have no desire to repeat, caused by a mixture of being passed at speed by a high sided van, my own speed creeping up and towing 100% ratio. Having towed bangers/hotrods on Brian James/Ivor Williams trailers in my younger days, large four wheel drives aren't exempt from snaking, but they are certainly in a better position to hold it all straight in the first place.

If anyone has seen the YouTube video where a twin axle caravan drags a Renault back down a hill you will realise why weights are so important.
