I was doing some service on my brakes this evening and had an odd experience. I have not run into this in the 10+ years I've worked on various Japanese and American cars I've owned.
On the front brakes, I removed the caliper slide pins to clean and grease them (high temp silicone). Pads looked great! At 27K miles I estimate about 70 - 80% remaining. On replacement, I hand tightened the bolts (in unison to avoid tilting/binding) and then used a 14mm socket and ratchet. One turn top..then one turn bottom....back and forth until tight. Now the odd part, when I applied the torque wrench (20 ft pds) to the top bolt it went loose. At first I thought I had turned it the wrong way, I put the socket back on my wrench and tightened. It was really loose. I got it tight and then applied the torque wrench again. It again went loose. I tightened again with the wrench then the torque wrench and got it to 20 ft pds (click!). The bottom was normal, applied torque wrench a few quarter turns and it was tight.
On the passenger side, I experienced the same problem but on both bottom and top caliper bolts.
Moving on to the rear, the experience was completely normal. Hand tightened, tighten with wrench, apply torque wrench and with 1/8 of a turn hit 20 ft pds. Both sides.
Why would the front caliper bolts have this issue?
On the front brakes, I removed the caliper slide pins to clean and grease them (high temp silicone). Pads looked great! At 27K miles I estimate about 70 - 80% remaining. On replacement, I hand tightened the bolts (in unison to avoid tilting/binding) and then used a 14mm socket and ratchet. One turn top..then one turn bottom....back and forth until tight. Now the odd part, when I applied the torque wrench (20 ft pds) to the top bolt it went loose. At first I thought I had turned it the wrong way, I put the socket back on my wrench and tightened. It was really loose. I got it tight and then applied the torque wrench again. It again went loose. I tightened again with the wrench then the torque wrench and got it to 20 ft pds (click!). The bottom was normal, applied torque wrench a few quarter turns and it was tight.
On the passenger side, I experienced the same problem but on both bottom and top caliper bolts.
Moving on to the rear, the experience was completely normal. Hand tightened, tighten with wrench, apply torque wrench and with 1/8 of a turn hit 20 ft pds. Both sides.
Why would the front caliper bolts have this issue?
