Expert Answers about Mercury Grand Marquis

• Differences Between Firestone # F4107 and Air Lift # AL60798 Helper Spring for 2004 Mercury Marquis
• Other than the color, and the fact that they were manufactured by two different companies, the Firestone # F4107 and the Air Lift # AL60798 are pretty identical. Both springs kits have the same weight rating, and both are rated for air pressures between 5-35 psi. What makes the Air Lift product more attractive is its lifetime warranty, versus the 2 year warranty offered by Firestone. Also, the Air Lift kit is a few dollars less expensive, so the Air Lift # AL60798 would be my recommendation.
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