Time for brakes , opinions wanted

[Deadmilenko]

I would second this thread for any new updates. I too need to replace the pads and rotors on my 2000 LX470.

 

[Hornd]

Just got done doing Stop Tech slotted only rotors and their suggested pad for this kit the sport pads. I have used this setup on my Tacoma(front at least) and a 4th gen 4r we used to have. Loved the setup. Better braking power and no warped rotors.

StopTech 967.44017 Truck Axle Pack Amazon product ASIN B0143JB4NU
At the same time I worked with Toytec Lifts to test their SS line kit that they have for the 4th gen 4r. Same length front and extended rear lines. Fit worked out fine and the parts should be listed as fitting GX on their site.

I chose not to do the GX460 caliper upgrade because of the number of people complaining of squishy pedal post work completion. IMO to do that MOD right you need to swap the entire system since the 460 has increased size and volume of fluid. The 470 has a great system, just needed a little extra bite from the slotted rotors and improved pads.

Sure your Rotors are Warped?

Why Do Brake Pedals Vibrate? | PowerStop Brakes

Bad brakes are dangerous. If your brake pedal pulses or vibrates, you need to find out why quickly. Have a question? PowerStop can help.

www.powerstop.com

When you apply the brakes while driving and notice a wobbly pulsation coming from the brake pedal, you should determine the cause of the pulsating feeling.

Pulsating brakes can be felt in a shaking steering wheel, a pulsating brake pedal, or in the seat as it vibrates when braking. If you feel the brakes pulsate when coming to a stop, it’s most likely an issue with the brake rotors.

Applying the Brake: The Science of Stopping​

It is hard to imagine the energy required to stop a vehicle traveling at 110 mph. Kinetic Energy is ½ mass times the velocity squared: KE = ½ mv2. Stopping a 2500 lb car requires 352,800 ft-lb of energy, the equivalent of dropping the car from an 11-story building.


When you stop, almost all of this energy is converted into heat through the rotor in a very short time. Brake rotors are designed to get hot, often in excess of 1400° F.

Contrary to popular belief, the temperature does not cause the rotors to warp, and this is not the reason why you get pulsating brakes.

So what causes the brake pedal to pulse or feel like it’s vibrating?

Main Cause of Pulsing Brake Pedals

The answer to what is causing your pulsing brake pedal lies in understanding how friction works, and how high spots form on the rotor to cause the pulsating brakes. There are two primary mechanisms of friction at work during the stop: adherent friction and abrasive friction.

• Adherent Friction: For adherent friction, a thin layer of material is continuously transferred between the brake pad and the rotor. The breaking of the chemical bonds creates a resistant force to stop the vehicle.
• Abrasive Friction: Abrasive friction is the mechanical wearing of the rotor and friction surface, like sandpaper on wood.

High Spots on the Rotor​

Brake pads use both adherent and abrasive friction, but at higher temperatures, adherent friction is what stops the car. The brake pad deposits material on the rotor, and as the pad gets hot, more material gets deposited. These deposits are caused by the resin (glue) in the pad.

All brake pads use a binding resin that holds the friction component materials together. This resin turns to liquid as the pads get hot, and the resin material along with some other material in the pad gets deposited on the rotor.

On overheated rotors, you can sometimes see the glazed resin material. It can look like someone brushed syrup on the rotor. The resin glazing forms a high spot on the rotor surface.

Another way to form a high spot on the rotor is if you clamp down on the brake after a hot stop.

When the brake pad gets hot, it wants to transfer friction material to the rotor and it does not care if the rotor is stationary or rotating. If you are at a standstill, the pad will imprint material on the rotor in the shape of the pad. The next time you brake, as the pad passes over the high spot, the temperature increases relative to the rest of the rotor. This causes more material to get deposited on this spot until it gets high enough to cause pulsating brakes.

It does not take a lot of material to cause this brake judder, only .0007 inches is enough to start to feel the pulsation.

PowerStop friction is engineered with lower resin content to maintain a uniform boundary layer of friction on the rotor.


Another way to prevent glazing or non-uniform friction deposits is to install drilled & slotted rotors. Powerstop’s drilled & slotted rotors help keep the pad cooler to prevent pad glazing.