ProSlip PIN prevents fretting corrosion,…..what IS fretting corrosion and what does it look like?
Fretting is a mechanical term describing small,repeated heavily loaded movements between two surfaces – typically metal surfaces. This is the type of movement which occurs when you hit the brake pedal many times during a trip in your car or van. Each time you press the pedal hydraulic pressure forces the piston against the pad and squeezes the disc. The piston only moves very very slightly as the pad is already in contact with the disc. The caliper pin distributes the force on each side of the disc equally. Brake judder is a sign the caliper pin is not sliding freely as the force on one side of is larger than on the other – this happens when the caliper pin lube has dried out.
The pin is in contact with the metal pin seat. Repeated braking means it moves against the pin seat in short sharp movements – this happens thousands of times.Using the wrong lubricant – e.g. silicon grease – will not protect the metal surfaces which will gradually show pitting at the surface. This pitting attracts corrosion, and reduces the effectiveness of the lubricant. ProSlip PIN contains Lithium which protects metal surfaces from high pressure forces. Lithium is used widely in greases because of this quality.