Rear Brakes Sqeak

When i drive my rear brakes sqeak so i replaced the bushing around the caliper bolts and re-lubricated the bolts it slides on but after every rain it sqeaks again. I dont know if I should be using a diferent kind of lubricant or what. does anyone have any input or had the same problem. I have relubricated the caliper bolts multiple times only to have the same problem in a few months.

Have you checked the bearings they will squeak if dry. Are the anti rattle clips installed.

The bearing are fine and the anti rattle clips are secure but the pins/ bolts that hold the caliper to the backing plate come with a little packet of lubricant that you put on the pins and i have to keep relubricating the pin/bolts. After about 6months or a big rain they start sqeaking because the caliper isnt floating on the pins and the brake pads rub the rotor uneven and cause a sqeaking noise. Any inout would be great.