Rack and pinion boots, or bellows, seal the inner tie rod with the rack and pinion unit to provide protection from dirt, dust, water and other debris particles. They prevent contamination and damage to the in-line ball joint on the tie rod and steering rack components.
As the steering wheel is turned, the rack and pinion unit’s two ends move side to side to steer the vehicle’s wheels. The boots “accordion” in and out with the inner tie rods to maintain their protective seal.
Rack and pinion boots are made from a variety of rubber or polymer compounds (polyurethane) that offer different performance characteristics, depending on the design need.
Rack and pinion boots should be inspected for damage with every oil change and replaced as necessary.
RACK AND PINION BOOT REQUIREMENTS FOR OPTIMAL LIFE
• High- and low-temperature resistance
• Retain flexibility over a wide temperature range
• Puncture, abrasion and chemical resistance
• Resistance to extension, compression and bending fatigue
• Seal integrity on the tie rod shaft and rack and pinion housing