Advice on brakes and pads

[Thresher]

I forget what pads I have (some ceramic OEM replacement ones not from Nissan...Wagner maybe?), but I went with the OEM style Brembo rotors. Nice slabs of cast iron that are vented in the center. They were relatively cheap, and they've done well. My pads are near the end, and I'll probably try some Hawks this time around.

I still laugh at the time the stealership tried to con me into buying new rotors.
Stealership - "Your rotors are rusty and need to be replaced, sir."
Me - "They're pretty new and made of cast iron, so...no".
Had they installed new ones, they'd probably have looked the same in 24 hours or so. Heck, driving through a puddle would have rusted them.

[THE_FRUITY_ONE]

Most braking systems aren't anywhere near stressed in daily life. Your biggest concerns will be for the life of the pad and the rotor in daily duties. This is why some brake systems can go near 20,000 miles if not ridden constantly and driven right.

In fact, the street pads on my TransAm GTA are over 5 years old and I still have near 1/4" of life left on the pads.

The rotors are finally beginning to show some cracks though, so its time to replace them.

I never cut rotors, I always replace them and turn the cores in. If you cut material off the rotor, your pedal will engage lower because more fluid is required as the brake pistons will need to extend further. Cutting a rotor also reduces the rotors ability to act as a heat sink. So if you are thinking about towing, or any performance use of your car/truck then do not cut rotors, ever.

Do the brakes on your budget. Tires and Brakes should be among your first "mods" even on a daily driver. Better tires = less stopping distance and better handling for emergency maneuvers. Better brake pads with a higher friction coefficient require less pedal effort for the same stopping effort and less stress on the rotor increasing its life.

By "mods" I don't mean all out performance stuff, but just good quality OEM replacement, not the $10 pads between you and that little kid in the street.

[dracom_ma]

I never cut rotors, I always replace them and turn the cores in. If you cut material off the rotor, your pedal will engage lower because more fluid is required as the brake pistons will need to extend further. Cutting a rotor also reduces the rotors ability to act as a heat sink. So if you are thinking about towing, or any performance use of your car/truck then do not cut rotors, ever.

That's not true actually. The brakes should automatically adjust themselves to compensate for the distance. It's the same thing that happens as the pads wear down and why you have to push the pistons back into the calipers when you change pads.

But I do agree that it's better to just replace the rotors instead of turning them.

[red_dog007]

Do the brakes on your budget. Tires and Brakes should be among your first "mods" even on a daily driver. Better tires = less stopping distance and better handling for emergency maneuvers. Better brake pads with a higher friction coefficient require less pedal effort for the same stopping effort and less stress on the rotor increasing its life.

Yeah, I recently started driving the Buick. My old S10 I put higher quality stuff on it. Now that I drive the Buick full time, brakes aren't as good as they need to be with me driving. They don't need to be changed, but to accommodate my driving new will really help me out. Then the Outlander we just bought, I knew it needed brakes before we bought it.
Just did a quick price at tirerack or Brembo and Hawk HPS, basically ~$200 for both vehicles. Amazon should be a little cheaper.

The Outlander could use tires, but I think it can make it to 100,000 miles with the current tires. Get new tires when I change the timing belt and all that jazz. I actually am looking into and hoping that I can get a 2 inch lift on it with A/T tires, and drop in a 4g63t. 140hp is just rubbish in the thing.

[Gordo]

What you want/need is going to depend a great deal on what you want from your brakes - if it's just running around town then some stock pads and discs will be a very good idea but if you're a hard driver, drive an automatic in hill country or otherwise stress your brakes then a harder/more heat tolerant pad material would be useful to reduce brake fade.
As for discs, a reputable OEM style replacement should be adaquate and grooves will improve wet response in some cases as they'll disipate the moisure film into the grooves - there is some arguement that they help reduce fade by feeding cooler air to the pad face, but that's questionable. As has been said several times, drilled discs aren't for the road as they will promote cracking, it can be reduced by countersinking or casting the holes in, though.
There are some pad materials that are advertised as being low dust, this may be important if you are concerned about appearances but I don't know how heat tolerant they are. On that subject, be aware that some (most) semi-metallic pads will leave brake dust that can cause unsightly staining of the rims.

Lastly, and I consider this very important, whenever changinging pads it's a good idea to change the brake fluid as well - most manufacturers have a 2 or 3 year change point and this usually is roughly the pad life - more important in wet or humid environments and should pay for itself in reduced cylinder/caliper/mastercylinder corrosion which will result in new components being required.

[THE_FRUITY_ONE]

That's not true actually. The brakes should automatically adjust themselves to compensate for the distance. It's the same thing that happens as the pads wear down and why you have to push the pistons back into the calipers when you change pads.

But I do agree that it's better to just replace the rotors instead of turning them.

Actually its 100% True. A modern brake system is a hydraulic system. You have a master, and several slave cylinders.

If your pads are low, the slave cylinders must extend further to apply the same braking force. This uses more volume of brake fluid. It also results in a lower engagement point, so the brake pedal must travel further to apply the same braking force as more fluid is in the system instead of residing in the master reservoir.

Works the same with hydraulic clutch assemblies too. Although since hydraulic clutch assembles are engaged by default (opposite of brakes) then the engagement point actually gets higher vs lower.

[dracom_ma]

Actually its 100% True. A modern brake system is a hydraulic system. You have a master, and several slave cylinders.

If your pads are low, the slave cylinders must extend further to apply the same braking force. This uses more volume of brake fluid. It also results in a lower engagement point, so the brake pedal must travel further to apply the same braking force as more fluid is in the system instead of residing in the master reservoir.

Works the same with hydraulic clutch assemblies too. Although since hydraulic clutch assembles are engaged by default (opposite of brakes) then the engagement point actually gets higher vs lower.

I'm sorry, but that is still incorrect.

The way modern brake systems work is that as the brake pads wear down, the pistons get extended further to compensate. Fluid is moved from the master cylinder to the calipers to do this as you press the brakes, but when the brakes are released, only the fluid needed to disengage the brake is released back. The engagement of the brake pedal stays the same throughout the life of the pad because of this auto adjustment. If the engagement of your brakes is changing and you have a modern automobile, then there is most likely something wrong.

The same thing happens if you turn down your rotors. The brake pistons will extend far enough to engage the brake, but only release enough to disengage the brakes, not fully retract back into the caliper.

Take a look at the master cylinder over the life of the brake pads and you will see that the fluid gets lower in the reservoir. This is because the fluid is staying in the lines/pistons(slave cylinders) to compensate for the wearing down of the pads. When you change pads, you have to compress the pistons back into the calipers, which pushes the fluid back into the reservoir in order to give enough room for new pads.

Clutches are different in that they are usually a piston that operates a lever that opens and closes the clutch. The piston is either fully retracted or fully extended to operate, but never actually adjusts to the wearing of the clutch, so the engagement point of a clutch can typically change.

[Gordo]

Yup, you're wrong, Fruity.
Think of the situation when a pad is worn a bit, the pad and piston are moved out slightly there as well - I won't go into retraction methods here.
With hydraulic clutches, the pedal should also remain at about the same operating height as the clutch wears, or lift if anything as the fingers lift as the friction plate wears.
Main reasons seem to be to ensure the pads can't be pushed past their locating recesses with worn out friction material and maybe to ensure enough material to act as a thermal mass, resist cracking and ensure enough mechanical strength.

[THE_FRUITY_ONE]

Doesn't work that way on any of the cars I've done brake jobs on. Pads worn = lower pedal on all of them. Same for clutch pedals.

Always noticed a difference in pedal engagement height on any of the cars I've worked on. 93 Escort, 99 Sephia, 06 G6, 2001 contour, .... every car I've ever done brakes on has had a higher brake pedal engagement when new pads were installed and the pistons pushed back in to allow for the pads.

[RainWind]

Pads worn = lower pedal on all of them.

In theory that shouldn't be the case, but it sure feels that way. After a brake job I can tell a difference in the pedal.