If you are driving a truck for a living then it's your responsibility to know the weights. If you are overloaded you will get the fine. Go to a weigh bridge and find out
AGREE! Even the blokes at the weighbridge can tell you or help you with limits.
Also up to you to know your heights... When I worked at Chemtrans, the boss used to scream that I was stalling in the yard cause I dug out my tape measure to measure height and length of the unit for that day.
It wasn't so bad once you had 'your own' prime mover, but when you were chopping and changing it was always different. Specially when doing hazmat.
Then it was straight to the weighbridge at the front gate for all weights.
Then I was happy to leave the yard - total time "stalling" 20 minutes.