dba Brakes

Q. Why does my steering wheel shake when I brake?

Perhaps one of the most common complaints regarding a car’s braking system is that of a shudder coming from the disc brake rotors.

This occurs when the brake rotor becomes unevenly worn, causing the brake pads to contact high spots on the rotor surface resulting in vibration felt by the driver through the steering wheel.

Many people often refer to the rotors as being ‘warped’ in this situation, although the term is not always accurate.

The lateral runout from a poorly installed rotor may not be within the manufacturer’s specifications.

It only takes the brake rotor to be out by just 0.08mm in order to feel a brake shudder, and this will be measureable with a dial indicator. Overtime this will wear the brake rotors unevenly.

While not quite set in stone, a shudder through the steering wheel under braking typically refers to a front brake problem, while a shuddering pulsation through the pedal alone may indicate a rear brake issue.


Q. What if my steering wheel shudders while I’m not braking?

A shudder without the application of the brakes would inherently refer to a tyre or wheel balance issue, or an out of round wheel.


Q. If uneven wear causes brake shudder, how can I avoid uneven wear and brake shudder?

Since we know that uneven wear results in brake shudder issues as mentioned earlier, we can trace the root causes from uneven wear in the first place.

The most common of all brake shudder issues, comes from an uneven mounting surface on the hub face due to scale or rust deposits.

This scale develops naturally over time and must be cleaned, especially if the rotors are removed and/or replaced.



As per images above, the hub face image on the left hand side has all the hallmarks of a dirty hub face with uneven scale and rust deposits.

This must be cleaned / scrubbed thoroughly by using a small honing stone and some WD40 and/or some wet and dry sand paper - again using WD40. There should be no evidence of rust or scale left on the hub face or hub spigot as seen by the clean hub face image above on the right hand side.

The thorough cleaning of the hub face and spigot should be of standard practice whenever installing or refitting disc brake rotors.

Other causes include worn wheel bearings, improper calliper mounting as well as poor calliper piston function, and severe heat situations.

Upon replacement of a disc brake rotor, the use of the new DBA En-Shield coated rotor or Street Series rotor would guarantee the genuine OE direct replacement quality you would expect.

If you require more of a heavy duty application – our DBA 4000 series HD or T3 slotted rotors as seen below will never let you down.



In addition to a clean rust and scale free hub face, it is important to bed in your new brake pads properly with the correct procedure (included in all DBA kits) to initiate a uniform friction layer across the rotor face.

Getting overly eager and punishing your shiny new brakes to test their capabilities without having followed proper break-in, can cause extreme thermal shock resulting in uneven wear and even cracks in extreme cases.

Do be mindful that when it comes to your car’s braking system, the most important thing to remember is that safety comes first.

For more information visit: http://www.dba.com.au/

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