break or wear out prematurely. U-bolts and shackles that hold leaf-spring-packs
together break, coil springs crack or snap in two, and torsion bars break free
from their securing brackets in the vehicle’s frame.
Brake Damage
Brakes are overtaxed when a vehicle that is loaded beyond capacity has to stop.
Most small trailers do not have brakes of their own so the brake system of the
towing vehicle bears the burden of the entire load. The additional stress on the
brakes causes the friction material to overheat and harden or crystallize,
rendering it ineffective and unable to stop the vehicle. This condition causes
“brake fade.” When you press down on the brake pedal, no friction material
wear occurs because the crystallized friction material is too hard to wear away
when it comes in contact with the rotors or drums. The brake shoes or pads just
ineffectively slide against the rotor or drum surface like locomotive brakes (steel
on steel) and make lots of noise, but there’s no stopping power. Overheating the
braking system also increases the temperature of the brake fluid to the point
where it cooks the rubber seals and the entire system is compromised.
Transmission Overheating and Damage
An excessive load causes the transmission to overheat, which causes the
transmission fluid to reach temperatures that compromise the soft internal parts
such as rubber seals and clutches. The heat hardens the rubber seals, causing loss
of internal hydraulic pressure. In addition, the glue that secures the clutch
friction material to the steel backings hardens and clutch strength is
compromised. If you’re going to haul a trailer, install an auxiliary transmission
oil cooler.