A1 Cardone 21-4047 Power Steering Pump All units are built with 100% new O-rings and premium-grade Viton seals to prevent leaks. Viton does not break down at high temperatures like conventional seal material Every pump is computer tested to measure pressure, bypass, fluid flow, valve operation, steering effort and noise for guaranteed performance All critical components (campacs, spool valves, etc.) are triple-tested to ensure product reliability Units are supplied with 100% tested and calibrated pressure relief valves for guaranteed performance Shafts are surfaced to precise specifications to eliminate premature seal wear and extend pump life A whining pump is usually caused by air in the power steering system. Inspect the reservoir for proper fluid level. If fluid has foam or air bubbles present, air has entered the system or has not been properly bled (ensure all hoses/clamps are tight). Some systems require special vacuum bleeding procedures. The problem is most likely in the steering unitthe pump does not know left from right. Check for binding steering components and repair as necessary. Use the correct fluid type that meets O.E. specifications for your vehicle Flush system with fluid to remove debris and contamination Install a filter to eliminate potential restrictions from debris Check for collapsed hoses that could potentially cause a restriction Always replace sealing O-Rings Never use Teflon tape as an attempt to seal fittings Leaks Lack of power assist while turning the wheel Whining, groaning or squealing noises from the pump Power assist only with increase in engine rpm