This is a simple mod that increases the cargo weights. for V 1.3.1 which has the individual cargo and trailer weights.
I have left the separate trailer weights as default and only increased the weight of the actual cargo.
All cargo has been increased by 35% except the loads marked “heavy” which have been increased by 50%
Please note that in the freight market each job has a weight indicated in brackets, That weight is the original cargo weight not including the trailer. I can’t see any def file to change those. So any load marked heavy is 50% higher and all others are 35% higher than the value shown