Some Toyota 4Runner owners report experiencing recurring front caliper seizure, which can lead to serious safety risks such as uneven braking, excessive heat buildup, and complete brake failure on one wheel. This issue has resulted in significant repair costs for some owners, particularly when caliper pistons seize up. Many owners recommend replacing front calipers instead of attempting to rebuild them, as rebuilding may not provide a long-term solution. Additionally, challenges with warranty coverage for caliper issues have been reported, even when maintenance was performed at the dealership. To mitigate costs, some owners have found success using remanufactured calipers from reputable sources, as OEM parts may not always be available. Regular maintenance and proper bleeding of the brake system are essential to prevent caliper seizure, and persistent issues may indicate problems with the master cylinder or other components. Symptoms of caliper issues include the vehicle pulling to one side, overheating brake smells, uneven pad wear, and warped rotors, which should be inspected to ensure proper caliper function.