With the rotors and hubs checked for excessive run-out, it's time for Samuel to move on to the brake pads. The set we selected for this vehicle are the Hawk HPS Performance Brake pads. We have had these on previous family vehicles and even my wife noticed the difference. She specifically requested these pads for the van.
The Hawk HPS pads feature a Ferro Carbon compound that give you nice initial bite, a high level of friction when hot or cold, built in shims, and a smooth, firm, pedal feel.
Even before the caliper started binding, she complained that the previous brakes felt "soft or mushy" and that was when the brakes were new. Installing the Hawk HPS pads has vastly improved the feel and performance of the brakes.
After this brake job, she says she feels a lot safer and more secure with this specific rotor and pad setup.
I'd also like to point out, I personally selected and purchased the pads, rotors, and fluid for this brake job out of my own pocket. These items were not provided by the manufacturers as samples etc...
Step 1: Double And Triple Check the Pads
Samuel pulled the pads out of the box and carefully inspected them again to make sure they were the correct size, shape and model. These come nicely packaged with the installation instructions and burnishing bed-in) procedures right on the box. That's a nice touch for sure!
The shims on these pads are actually riveted to the back of the backing plate so they are secure and won't slide around. They also look to be a lot larger than the O.E. shims. We later found them to be very quiet even during the bed in procedure. There wasn't a hint of noise when braking. They also have the factory style wear indicators on the inboard pads. These were a perfect match for the O.E. calipers.
Step 2: Replacing Clips And Loading The Hawk HPS Pads
Samuel then replaced the small, steel noise elimination clips on the caliper brackets with new ones. These came with the caliper hardware kit we purchased at a local parts store (the same kit that had the caliper pin bushings and boots).
They appeared to be in good shape but these small clips should always be replaced. They will help eliminate vibrations and noise and they are inexpensive parts. Brakes develop a lot of heat and these small steel parts will fatigue as they get old. Replacing these small metal clips and pins is cheap insurance against noise issues.
With the new clips in place, Samuel then loaded the new pads into the caliper bracket and checked the clearances by sliding the assembly into position over the ATE brake rotor.
Make sure you don't get any grease or other contamination on the brake pads as you handle them. Any contamination on the face of the pads can interfere with the bed-in process.
Step 3: Bolting Up The Caliper Bracket
The pad and bracket clearance checked out so he inserted the caliper bracket bolts and snugged them by hand being careful not to cross thread them. The manual also recommended lightly coating the bolt threads with medium strength thread lock compound which he applied before installing them.
Once they were snug, he torqued the bolts using a Gorilla Hand Torque Wrench to the specific torque setting listed the vehicle shop manual.
Always follow the proper torque specs and instructions in your shop manual! Failure to do so can lead to brake damage or failure! Don't take chances with your brakes.
Step 4: Prepping The Caliper
The brake caliper piston needed to be retracted so it would fit over the new brake pads and rotors.
Check your vehicle's shop manual for details on the proper procedure for your calipers.
Some pistons (typically on rear calipers) need to be twisted back into the caliper. Others, like the front calipers on our Grand Caravan simply push back in place.
To handle this task, Samuel used his great-grandfather's trusty , rusty c-clamp.
Something tells me this may have made its way home in grand dad's lunch box when he was still working at Studebaker.
It's a good idea to siphon some of the brake fluid out of the master cylinder before you do this. That way it won't overflow into your engine compartment as the fluid is forced back up the lines. Also note the caliper is still supported by the spring to make sure there is no tension on the brake line.
Step 5: Installing The Caliper
With the piston retracted, the caliper slides right over the pads and rotor.
Again, Samuel coated the caliper mounting bolts with thread lock compound and snugged them up by hand. Then he torqued them to the specified torque setting in the shop manual.
Step 6: Repeat The Same Procedures On The Other Side
With the caliper on, he removed the wheel nuts and the extra washers from the hub and rotor. The rotor would stay in place as he moved on to the other side of the van.
The other side went a little quicker since the rotor wasn't overheated and fused to the hub. Again, he changed gloves frequently to keep the new pads and rotors free of any contamination as he worked. He was then ready to start bleeding the brake lines in our final installment:
Disc Brake Challenge Part V: Bleeding The Brakes And Bedding-In The Pads