Frequently Asked Questions - Brake System
The Anti-lock Brake System (ABS) does not function under 6mph (10kph).
The ABS system performs a test the first time the vehicle reaches 4mph (6kph) after starting which produces a mechanical noise. This "click" is normal.
It is an indication your brakes are nearing their wear limit. The squeal tab on one of the pads is just barely dragging on the rotor and vibrating to produce the sound. When you apply the brakes you're deadening the vibration and the sound goes away. As the brakes heat up the clearance between the tab and the rotor increases a smidge and it doesn't drag with the brakes off and stays quiet.
hey contain the hydraulic pressure to a better degree than stock rubber hoses (thanks to the braiding, they don't expand as much when the brakes are applied). This gives a firmer pedal feel and increased pressure at the brakes, for better stopping.
The braided covering also serves to protect the hose against sharp objects and abrasion.
They typically come in sets of three - two for the front (one for each wheel) and one for the rear (located centrally on a "T" connector).
Any decent DOT 3 brake fluid can be used.
Always use fresh brake fluid and never re-use old brake fluid! Keep container tightly capped when in storage.
The front brake pads minimum thickness is 2mm and the rear brake shoes is 1.5mm. Any less and they must be replaced. Inspect regularly at 20k mile intervals.
Do not allow brakes to go unserviced or you will cause additional wear at additional cost to fix (such as scoring the rotors, typically happening at the stage where the front brakes squeal and screech when applied).
Caution:
- Carefully monitor brake fluid level at master cylinder during bleeding operation.
- If master cylinder is suspected to have air inside, bleed air from master cylinder first.
- Fill reservoir with new brake fluid (DOT 3). Make sure it is full at all times while bleeding air out of system.
- Place a container under master cylinder to avoid spillage of brake fluid.
- Turn ignition switch OFF and disconnect ABS actuator connectors or battery ground cable.
- Bleed air in the following order (does not seem intuitive, but this is correct for the Xterra):
- Left rear brake
- Right rear brake
- Right front brake
- Left front brake
Procedure:
- Connect a transparent vinyl tube to air bleeder valve.
- Fully depress brake pedal several times.
- With brake pedal depressed, open air bleeder valve to release air.
- Close air bleeder valve.
- Release brake pedal slowly.
- Repeat steps 1. through 4. until clear brake fluid comes out of air bleeder valve.
- Tighten air bleeder valve to specified torque. 61-78 in/lbs.
If you just change the brake pads you normally shouldn't have to bleed the brakes. After changing the pads the pedal will be soft, pump it 4-5 times slowly and fully.
Normal soap and water will usually remove brake dust from your wheels. If a sponge doesn't remove the buildup, a brush may be used. Regular cleaning of the wheels will reduce buildup much better than occasional, harsher cleaning.
Use wheel cleaners only when absolutely necessary and take care to use the correct type. Failure to do so will lead to damage of the painted finish on the wheels and center caps. Flush wheels very thoroughly after application.
This is normal if the vehicle has sat for any length of time in a humid environment as the rotors will quickly form surface rust. It will quickly vanish with use of the brakes under normal driving circumstances.
The brake drums will also behave in this manner, but these surfaces are out of view.
Typically, every 20,000 miles the brakes (e.g. pads, rotors, shoes and drums, etc.) should be inspected for wear and replaced/repaired as needed.
Aftermarket components include a rear disc brake conversion kit, upgraded rotors and pads as well as stainless braided brake hoses.
The Xterra features disc brakes in the front and drum brakes in the rear with power assist and anti-lock (ABS).
