Vehicle: 2005 Toyota Sienna, rear drum/front disc, no VSC(Toyota/Denso/Advics implementation of ESP).
I’ve noticed a squeal from the front brakes when the van is in stop & go traffic - this happened in the line waiting to get into Yosemite two weeks ago. Else, the van stops fine and the noise goes away and stays gone. Yesterday, my parents drove the van and the noise was back. My dad chalked it up as weird but normal braking behavior, my mom was panicking and called me in a tizzy while I was out on the river with friends for the day.
The brake pads installed are Toyota “warranty” pads, made by Advics with a FF friction level. I didn’t note the formulation number. 8mm left, so plenty of life. I took the front brakes apart, sanded the pads on a flat piece of marble with 150 grit sandpaper. Installed new aftermarket abutment clips, put a thin smear of Permatex moly silicone gray brake lube on the backs of the clips, as well as the “ears” of the calipers where they touch the outboard pad and on the piston. Noticed the passenger outboard shim sandwich fell off, so I bent the tangs to secure them back on, with a few dabs of lube between the shims and backing plate. Took the van out on a drive, brakes feel fine - I will note a local machine shop turned the rotors when the pads were replaced and there was a bit more runout than I would have liked.
Now, while Japanese cars use NAO “ceramic” friction that works on the cohesive friction principle, shouldn’t there be a microscopic(as in microns) layer of friction on the rotor at all times that’s constantly renewed when the brakes are applied? What else would cause this low-speed brake squeal?
I’ve noticed a squeal from the front brakes when the van is in stop & go traffic - this happened in the line waiting to get into Yosemite two weeks ago. Else, the van stops fine and the noise goes away and stays gone. Yesterday, my parents drove the van and the noise was back. My dad chalked it up as weird but normal braking behavior, my mom was panicking and called me in a tizzy while I was out on the river with friends for the day.
The brake pads installed are Toyota “warranty” pads, made by Advics with a FF friction level. I didn’t note the formulation number. 8mm left, so plenty of life. I took the front brakes apart, sanded the pads on a flat piece of marble with 150 grit sandpaper. Installed new aftermarket abutment clips, put a thin smear of Permatex moly silicone gray brake lube on the backs of the clips, as well as the “ears” of the calipers where they touch the outboard pad and on the piston. Noticed the passenger outboard shim sandwich fell off, so I bent the tangs to secure them back on, with a few dabs of lube between the shims and backing plate. Took the van out on a drive, brakes feel fine - I will note a local machine shop turned the rotors when the pads were replaced and there was a bit more runout than I would have liked.
Now, while Japanese cars use NAO “ceramic” friction that works on the cohesive friction principle, shouldn’t there be a microscopic(as in microns) layer of friction on the rotor at all times that’s constantly renewed when the brakes are applied? What else would cause this low-speed brake squeal?
