Hi,
I had a blow out on a tandem a few years back, scary but not a major drama. After this I did some research and discovered that a lot of LT tyres are rated to around 700 or 800kgs (and non LT's are much less) so if you only have one axle the tyres could be very easily overloaded
The calculation of a vehicle's tow rating is a complex calculation that includes many things other than just power and strength, radiator cooling capacity is one of them. As an example the 2012 Lexus IS250 had braked towing capacity of 1500kgs but the more powerful IS350 was not approved for towing.