Air Suspension Parts for Mercedes 2016 GL450: A Complete Guide

If you own a 2016 Mercedes-Benz GL450, you know that the air suspension system delivers a smooth, controlled ride. But when components start to fail—whether it's a leaking air spring, a noisy compressor, or a faulty valve block—you need reliable replacement parts. This guide covers the essential air suspension parts for the 2016 GL450, explains common symptoms of failure, and helps you choose between OEM and aftermarket options.

Understanding the Air Suspension System on the 2016 GL450

The 2016 GL450 uses Mercedes' AIRMATIC system, which replaces traditional steel springs with air springs (also called air struts or air bags) at each wheel. The system includes an electric air compressor, a valve block, height sensors, and control modules. When you start the car, the compressor pressurizes the system, and the valve block distributes air to each corner based on ride height and load.

Key Components

• Air Springs (Struts): The rubber-and-plastic bellows that hold the vehicle's weight. Front struts often combine the air spring with a shock absorber; rear springs may be separate from the shocks.
• Air Compressor: An electric pump that generates compressed air. It typically includes a dryer (desiccant) to remove moisture.
• Valve Block: Manages air distribution to each spring. Some models integrate the valve block with the compressor.
• Height Sensors: Usually one per corner, these tell the control module the ride height.
• Air Lines and Fittings: Connect components; can crack or leak over time.
• Control Module: The brain of the system. It reads sensor data and commands the compressor and valves.

Common Air Suspension Problems on the 2016 GL450

Air suspension issues on this model often appear around 60,000–100,000 miles. Common symptoms include:

• Vehicle sagging overnight: Usually a leaking air spring. The rubber can develop cracks or pinholes.
• Compressor running too often or not at all: A failing compressor, moisture damage, or a clogged air filter.
• Uneven ride height: May indicate a bad height sensor, leaking line, or stuck valve.
• Check engine / suspension warning light: The system monitors faults via OBD-II codes.
• Noisy compressor: Worn bearings or internal damage.

Diagnosing the Issue

Before buying parts, confirm the source. Use a Mercedes-compatible scan tool to read fault codes (e.g., P1765 for compressor run time). Visually inspect air springs for cracks or splits. Listen for air leaks using soapy water. A quick test: park on level ground, measure ride height (fender to wheel center), then check again after a few hours. A drop of more than 1 inch suggests a leak.

OEM vs Aftermarket Air Suspension Parts for the GL450

When replacing parts, you can choose between original Mercedes (OEM) and aftermarket brands like Arnott, Dorman, or Bilstein. Each has pros and cons.

OEM Parts

• Pros: Exact fit, same quality as original, easy warranty claims through dealer.
• Cons: Expensive—a single front air strut can cost $800–$1,200; compressor around $900.
• Best for: Owners who plan to keep the car long-term and want guaranteed compatibility.

Aftermarket Parts

• Pros: Lower cost—many quality aftermarket air springs cost $300–$600 each. Some brands like Arnott offer a lifetime warranty.
• Cons: Fit and performance can vary. Some aftermarket compressors may be noisier or less durable.
• Best for: Budget-conscious owners or those with older, high-mileage vehicles.

Important: For air springs, Arnott is a trusted brand that rebuilds OEM units. For compressors, Dorman offers a remanufactured unit that includes a new dryer. Bilstein makes aftermarket shocks that can replace the air struts when converting to conventional suspension, but that's a different project.

Recommended Air Suspension Parts for 2016 GL450

Based on common failures and owner feedback, here are specific parts to consider.

Air Springs (Front and Rear)

• Front Left (Driver Side): Arnott A-2795 (new) or A-2796 (remanufactured). Includes air spring and shock absorber assembly.
• Front Right (Passenger Side): Arnott A-2800 or A-2797.
• Rear Springs: Arnott A-2543 (new) for the rear. Note: the GL450 has separate rear air bags (no integrated shock). The shock absorber is a separate part (e.g., Bilstein 24-237218).
• OEM: Mercedes part numbers 166-320-01-25 and 166-320-02-25 for front; rear springs are 166-320-07-25.

Air Compressor

• Aftermarket: Dorman 949-533 (includes new dryer). Also available as a rebuilt unit from Arnott (C-2650).
• OEM: Mercedes part 166-320-00-04. Expect to pay $700–$900.

Valve Block

• Aftermarket: Arnott C-2651 (includes valve block and lines).
• OEM: 166-320-15-04.

Height Sensors

• Aftermarket: Hella (e.g., 6PF 009 114-241) or Febi Bilstein. Cost ~$40–$60 each.
• OEM: A 220 542 00 18.

Air Lines and Fittings

• Kit: Dorman 950-501 (air line repair kit with connectors). For individual lines, use 4mm nylon air line (sold by the foot).

Installation Tips and Considerations

Replacing air suspension parts on the GL450 is moderately difficult. You'll need basic hand tools, a jack, and jack stands. Some key points:

• Safety first: Depressurize the system by removing the fuse for the compressor (fuse 40 in the rear fuse panel) and opening a door to vent air.
• Front strut removal: Requires compressing the air spring (if new) or lifting vehicle to release tension. Unbolt the lower control arm and sway bar link.
• Rear air bag: Jack up the body, remove the lower bracket, and deflate the bag. The bag slides off the upper mount.
• Compressor replacement: Located under the vehicle near the rear passenger side. Disconnect lines, electrical connector, and mounting bolts.
• After installation: Reinitialize the system with a scan tool (or drive slowly to let it self-level). The car may sit low for a few minutes.

Cost Comparison

Replacing all four air springs and the compressor with aftermarket parts can cost about $1,500–$2,000 in parts alone. OEM equivalent would be $3,500–$5,000. Labor at a shop adds $500–$1,000. Doing it yourself saves labor but requires patience.

Final Recommendation

For the 2016 Mercedes GL450, the most common failure is air springs, followed by the compressor. If you're on a budget, go with aftermarket air springs from Arnott (A-2795 / A-2800 front, A-2543 rear) and a Dorman compressor (949-533). These offer reliable performance at half the cost of OEM. Always replace the dryer or compressor in pairs to avoid contamination. Check the valve block only if you suspect cross-leaks. If you want peace of mind and plan to keep the car for many years, OEM parts are available but expensive.

Before ordering, confirm your VIN to ensure compatibility. Some GL450 models have optional adaptive damping (ADS) which uses different struts. If your car has ADS, the part numbers differ.

Tip: Buy from a reputable supplier like FCP Euro, RockAuto, or Pelican Parts. They often include warranty and have good return policies. Avoid no-name brands; the cost savings aren't worth the risk.

By understanding the system and choosing wisely, you can restore your GL450's air suspension to like-new condition without breaking the bank.