Been dealing with a left rear wheel/brake problem that randomly appears then disappears. Without applying brake, left rear wheel shudders like the brake pad is engaging and releasing repeatedly causing a shuddering sensation. More noticeable when braking. Can last a few minutes to 4 or more miles. Stopping for 30+ minutes usually cures the problem until the next random occurrence. Brake rotor/caliper/pad system has been thoroughly analyzed and even replaced components to no avail. Any chance its the ABS system going rogue? Should I start by replacing the wheel speed sensor? Had this 2006 since day 1 and want to keep it but cant trust it now.