Welp, I dove into the van's brakes again.
Inspected the caliper slide pins on all 4 corners to make sure they moved freely. Lifted the calipers and made sure the pistons advanced, since I pushed them in all the way to make clearance for the thicker pads. I was thinking the pulsation was caused by a stuck piston, but my inspection and the way the van traveled down the road suggested that the calipers weren't the culprit.
I did, however, replaced both the front rotors. Instead of sticking to Powerstop, I decided to go with Raybestos.
This time, I didn't perform the bedding procedure as suggested by Powerstop. I will conform to the new car manual, which states no hard braking for the first 500 miles. When I went for a test drive, I sped up to 70 mph and gradually applied the brakes.
Smooth as silk. The "old" rotors produced violent shuddering that was very unnerving.
I then continued the 70 mph => 50 mph gradual stopping procedure about 8 more times. Hopefully, the brake material deposited evenly on the rotors' surface.
Anyway, thanks for all your help. I appreciate it.
