Tongue Weight
The vertical weight a trailer or trailed implement transfers to the hitch point. This load makes the tractor's rear axle heavier and its front axle lighter; when the limit is exceeded, steering control is reduced, and in extreme cases the tractor becomes light at the front. The permitted tongue weight of the tractor is specified by the manufacturer.
The vertical load changes with the trailer's load distribution: when the load is stacked towards the front the vertical force at the hitch point increases, when it is moved back it decreases, but this time the trailer starts to sway. The correct setting is finding the balance between the two.
- When the front axle becomes light, braking distance increases and steering response deteriorates.
- If necessary, regain the balance by fitting front weights.
- Distribute the load evenly inside the trailer and secure it; a shifting load changes the tongue weight while driving.
None of these values are changed by electronic linkage control. A retrofit kit changes the way the linkage is moved; the tractor's axle loads, towing limits and balance rules stay exactly the same. If you are towing a trailer while a heavy implement hangs on the linkage, assess both loads together.
Context in which this term is used: Converting a tractor hydraulic lever to electronic control