| Term |
| Coupling load | Load that the trailer tow-bar places on the 'gooseneck' |
| Permissible trailing load | From the manufacturer stipulated maximum weight of a hitched up trailer. |
| Braked trailing load | The braked towing weight is mostly much higher or even
twice as high than the unbraked weight. |
| Maximum permissible gradient | Allowed towing weight is calculated by the manufacturer on different inclines. |
| Rear axle load | The portion of the total weight which effects the rear axle complemented perhaps by the coupling load. |
| Increased trailer-load | For increased towing weight, the tractor load must be reduced or even completely done without. |
| Gross weight (tractor & trailer) | The weight of the tractor vehicle plus trailer. |
| Load distribution | A coupling load very near to the permissible value is recomended. |
| Weight relationship | Rather load the tractor vehicle to capacity than the trailer. |
