Brake Inspection

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Brakes

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Service

Proper brake system maintenance is very important both for the longevity of your 350Z and for the safety of you and others on the road. Inspecting your 350Z brakes is very easy and should be done ever 5 to 10 thousand miles depending on your driving conditions. Those who take their 350Z to the track should inspect them after every track day.

1 Brake Pad Inspection
2 Brake Rotor Inspection
3 Brake Fluid Inspection
4 Parking Brake Inspection

Brake Pad Inspection

Also See: Brake Pad Installation, Brake Pad Bedding

Good Pads (top) Worn Pads (bottom)

There are a few telling signs that you need to replace your pads. First, check the manufacturer's suggested pad lifespan. Some manufacturers give an estimate on how long the pads will last, given in thousands of miles. However this is just an estimate. If you do a lot of highway driving you could easily extend the life. On the other hand, if you enjoy spirited driving or the occasional run at the race track expec pad life to be shortened.

The next sign is grooves cut into the rotor. This can be a sign of a damaged pad which may be dragging unwanted material across the brake rotor. It could also be a sign that your pads are completely worn away. Depending on how deep the grooves are, the brake rotors may be too damaged to repair.

Of course the obvious is pad thickness. Sometimes this can be difficult to judge while the wheels and tires are on the car. If you can see them easily, then make sure there is sufficient thickness. New pads are approximately 1/2" thick, so if yours are 1/4" thick or less you need to change them.

The last and most severe sign that your pads need replaced, will be severe squealing or grinding noises when you apply the brakes. Allowing your brakes to reach this point can be an expensive fix, as well as being unsafe to drive.

The only fix for damaged/worn brake pads is to replace them.

Brake Rotor Inspection

Also see: Brake Rotor Installation

Worn vs. New Rotors

Brake rotor inspection fits hand-in-hand with brake pad inspection, but there are some other signs to look out for. When you are driving your 350Z and apply the brakes, if you feel a shudder or ther car vibrates strangely your brake rotors may be warped. Warpage is due to the heat generated during braking. Low quality rotors are more susceptible to this type of heat damage than good quality ones. You might think you are saving a few bucks when buying cheap rotors, but you may end up replacing them more often than a more expensive set.

If your rotors have grooves cut into the surface, they are damaged. These are usually easily visible with the naked eye.

Another sign of worn rotors is a "ridge" or "lip" around the outer circumference. This is where the brake pads do not touch, so there is a "valley" where the brake pads have worn out the rotor surface. You can check this by rubbing your finger outward near the rotor edge.

Finally, there is the thin rotors. Once your rotors are so thin they must be thrown away. Rotors should have a marking on them with the minimum thickness allowed. Running them beyond this thickness could proove to be hazardous.

Unlike brake pads, brake rotor maintenance comes in two flavors: replacement and refinishing. Replacement is straighforward but some people may not know what refinishing means. You may run across several names for brake rotor refinishing including: turning, cutting, latheing, and resurfacing. Resurfacing rotors requires pulling them off of the 350Z and taking them to a mechanic shop that has the ability to do this procedure. This procedure cuts the old worn, warped, and grooved surface down to a new looking flat surface. Not all rotors will turnable. The mechanic will go by the minimum thickness callout on the rotor and let you know if he can proceed or not.

Brake Fluid Inspection

Also see: Brake Fluid Bleeding

Find the brake master cylinder. This is usually located under the hood on the driver's side of the car, toward the back of the engine compartment. Imagine where your brake pedal would end up if it went all the way through to the engine. The brake master cylinder is a small (about 6-by-2 inches), rectangular piece of metal with a plastic reservoir and a rubber cap on top, and small metal tubes leading from it.

Check your manual if you aren't sure that you've found the master cylinder. The rubber cap will usually read "use only DOT 3 or 4 brake fluid from a sealed container."

Note that on most newer cars the reservoir is translucent and you can see the fluid level without removing the cap. There will be a "full" line, the brake fluid should be at this line.

In older cars (pre-1980) the brake master cylinder reservoir may be made entirely of metal so that you must take the top off to check the fluid level. The top is held on by a metal clamp, use a screwdriver to pop off the clamp and lift the lid.

Add brake fluid to the "full" line. Use the correct brake fluid for your car: Check the rubber cap and your owner's manual to find out what grade of brake fluid your car requires. Most cars use DOT (Department of Transportation) 3 or 4. If the reservoir has 2 parts, fill both halves.

If the brake master cylinder is empty, the brake pedal will go to the floor. If this is the case, you will have to bleed the brakes in addition to adding fluid: Time to see your mechanic, who will flush and refill the braking system.
Brake fluid is very toxic. Keep it away from hands and eyes, and avoid spilling it on the ground. Dispose of empty containers carefully. Be especially careful not to spill brake fluid on your car's paint.
Wash your hands well after handling brake fluid.
Don't drive a car that has run out of brake fluid until bleeding the brakes.