IS200/2003/SE - 76000miles. Standard everything.
Front calipers are responsible for a host of unpleasant sounds usually at parking speed, can have feel of warped or uneven braking.
Now had the calipers off and serviced twice. Last set of pads went in we noticed the carrier was stiff and the pads worn unevenly. New pads and discs around 65000k.
Decided to give the calipers some love.
Bought a seal kit from bigred via ebay. Can confirm has everything needed and appears quality stuff. Did the work under the supervision of qualified engineer. Heres how it went.
Took out the pads, health set but worn unevenly.
Took off the caliper. With the caliper on the bench easy to test and see the carrier on both calipers were partially seized. Same slider on both sides. Seals in good condition. The bolts the carrier slide on are the offending items. One of the rubber boots gets stuck, allowing the surface of one slider to be corrupted and start to jam.
Buffed the bolts and cleaned everything, new seals, reassembled. Glad I watched someone else do the piston seals first as it a precision job. Back on car and also treated it to some new brake fluid... and bleed,,, and bleed.. and and and.... lots of unplesantness gone.
Conclusion -
The caliper seals are probably not the problem. Given the kit was £34.00 and I had the luxury of wiser hands than mine to help was cheap for me to do. Would guess most only need to pull to carrier off and polish up the carrier bolts to sort the problem. Pay attention to which bolt is top and bottom, one has a rubber seal at the end. Either each year and or each time pads/discs are replaced, polish the bolts and check the slider action.
Do have some pics if that would help.