Drums and Hubs

9-inch, 10-inch, and 12-inch Trailer Brake Drums

Brake drums are the primary element in the assembly of electric, mechanical and hydraulic trailer brakes.

Problems arise when electric brakes become hot. Hot brakes, worn shoes, and hot magnets are signs of wear.

Caravan Brake Drum Ratings (Pair)

• 9-inch Mechanical – 1450kg Max Load Capacity – 1200kg Max Braking Capacity
• 9-inch Hydraulic – 1450kg Max Load Capacity – 1450kg Max Braking Capacity
• 10-inch Electric – 1600kg Max Load Capacity – 1600kg Max Braking Capacity.
• 12-inch Electric – 2250kg Max Load Capacity – 2250kg Max Braking Capacity.

There are three leading causes of hot brake drums:

• Worn bearings
• Worn brake shoes
• Wrong size wiring

Brake parts, including drums, must be replaced due to wear.

We often hear wheel nuts coming loose on drums and hubs from caravanners on outback roads.

We discovered those caravanners who tightened their nuts every morning had no problem with broken wheel studs.

Those caravanners whose wheel nuts were falling off suffered damage and sheered off wheel studs.

One way to combat loose wheel nuts is to install wheel nut indicators.

The lesson learnt was to include a wheel nut tightening check on your rig each morning when driving on rough dirt and corrugated roads.

Understanding the Calculation

The Face to Face measurements to calculate Tip to Tip measurements are as follows:

• S/L 10-inch Electric Drum adds 103mm
• S/L 150mm Lazy add 100mm
• 10-inch Disk Rotor add 98mm
• PLL 10-inch Electric Drum adds 122mm
• 2T x 12-inch Electric Drum add 172mm
• 2T x 205mm Lazy add 172mm