The following external conditions affect brake performance:

1. Tires having unequal contact and grip on the road will cause unequal braking. Tires must be equally inflated, identical in size, and the tread pattern of the right and the left tires must be approximately equal.
2. A heavily loaded vehicle requires more braking effort. When a vehicle has unequal loading, the most heavily loaded wheels require more braking power than others.
3. Misalignment of the wheels, particularly in regard to excessive camber and caster, will cause the brakes to pull to one side.
4. Towing a trailer requires longer braking distances and tends to overheat the brakes sooner.