ACDelco Rear Air Lift Shock Absorber Gold 504-511 (88946598) — Adjustable 25–200 psi, 1,100 lb pair capacity

ACDelco Gold 504-511 (88946598) Rear Air Lift Shock Absorber is an adjustable air-assisted rear shock designed to temporarily level and stabilize a vehicle when hauling or towing heavy loads.

These ACDelco Specialty Air Lift Shocks add user-controlled air pressure to the rear suspension so you can tune ride height and handling for short-term hauling or towing needs. They are designed to be used only as a temporary aid—up to the vehicle's rated GVWR—and do not change the vehicle's factory payload rating. With an adjustable range from 25 to 200 psi and a paired load capacity up to 1,100 lbs, these shocks are built to give drivers more control over sag and stability when carrying extra weight in the rear.

How do these air lift shocks help when towing a trailer?

When a trailer or heavy cargo pushes down on the rear of the vehicle, the ACDelco air lift shocks let you add pressure to restore ride height and preserve the vehicle's intended suspension geometry. Maintaining near-level stance improves handling and reduces stress on bushings and mounts.

• Adjustable air pressure from 25–200 psi to match trailer weight.
• Up to 1,100 lbs pair capacity to resist rear sag under load.
• Helps stabilize alignment angles for safer steering response.

Will these shocks fit my vehicle and are they durable?

ACDelco Gold 504-511 is a vehicle-specific part engineered and tested to fit intended makes and models. Components such as a super-finished chromed piston rod are included to resist corrosion and extend service life under typical road conditions.

• Real-world tested for fit and application compatibility.
• Chromed piston rod for consistent wear surface and seal life.
• Designed for temporary load-carrying situations, not permanent modifications.

How do I adjust and use the air pressure safely?

Air pressure is adjusted to match the temporary load you’re carrying; increase pressure to raise the rear and reduce pressure when unloaded for a normal ride. Never exceed the vehicle’s Gross Vehicle Weight Rating (GVWR) and follow the manufacturer’s recommended maximums for this component.

• Adjust between 25 and 200 psi to tune ride height and firmness.
• Monitor vehicle stance and handling while adding pressure incrementally.
• Do not use to exceed vehicle GVWR; product does not increase payload.

What performance benefits can I expect during temporary hauling?

These shocks help limit bottoming out, reduce excessive sway, and lower the rate of wear on other suspension parts by maintaining proper ride height under load. Improved rear support gives more predictable handling when carrying heavy items or towing boats and trailers.

• Reduces risk of undercarriage damage from bottoming out.
• Helps reduce uneven wear on suspension components.
• Provides a more controlled, stable ride during short-term hauling.

Who is this for: The ACDelco Gold 504-511 Rear Air Lift Shock Absorber is aimed at vehicle owners who occasionally carry heavy rear loads or tow trailers and want a temporary, adjustable method to restore ride height and improve handling. It’s suitable for drivers who need a vehicle-specific, tested solution for short-term leveling—not for increasing permanent payload capacity. Installers and DIYers should verify vehicle fitment and follow all safety and weight limits provided by ACDelco and the vehicle manufacturer.