Stability Baseline

The COG is inside a tractor’s stability baseline. Drawing a line to connect all the wheels of the tractor forms the tractor stability baseline.

Three very important points to remember about tractor COG & stability baselines:

  1. The tractor will not overturn if the COG stays inside the stability baseline.
  2. The COG moves around inside the baseline area as you operate the tractor.
  3. A wide front-end tractor provides more space for the COG to move around without going outside the area of stability.


Tractor COG can move out of stability baseline when;

  • Operated on a steep slope.
  • Tractor’s COG is raised higher.
  • Tractor is going too fast for the sharpness of the turn.
  • Power is applied to the tractor’s rear wheels too quickly.
  • The tractor is trying to pull a load that is not hitched to the drawbar.
  • When a tractor is on a slope, the distance between the tractor’s COG & stability baseline is reduced.
  • On steep slopes, the tractor is already close to an overturn.
  • A small bump on the high side, or a groundhog hole on the low side, may be all that is needed for the tractor to overturn.