30 ton RGN load capacity

I hesitate to put this out there but most likely that trailer has as built a safety factor between 2 and 3….meaning it can probably hold between 60 and 90t without breaking….but that doesn’t account for wear and tear and rust and the life span of the trailer will be severely shortened.

 

I would not be concerned about a one-time overage of 10%. Even running something at or near but under the max consistently will wear it out faster than running in the middle or low end of a range. Like with the truck engine.

The trailer’s safety rating is vital for any carrier to understand its heavy haul trailer’s capacity clearly. The safety rating is an indicator that shows how much stress a trailer can handle. An accepted average is a 1.8 to 1 ratio, but some may steer towards a 2.5 to 1 for a broader cushion that considers all kinds of road dynamics.
Know what the trailer can handle before putting it between the road and the load | Trailer Body Builders

For example, wings of modern airliners are tested to withstand 150% of the limit load, which is a safety measure to ensure structural integrity under extreme conditions. But this is a temporary load and not a sustained one such as an excess load/stress from turbulence.

You can call the manufacturer and ask them.