2020 Chevrolet Silverado 3500HD A/C Refrigerant & Oil Capacity

Quick answer

• Refrigerant Type: R-1234yf
• Full System Charge: 22 oz (624 grams)
• PAG Oil Type: PAG 46
• PAG Oil Amount: 6.75 fl oz (200 mL)
• Low-Side Service Port Location: On the accumulator/drier, near the firewall, passenger side.
• High-Side Service Port Location: On the A/C line, near the condenser, driver's side top.

Why R-1234yf matters

The 2020 Chevrolet Silverado 3500HD uses R-1234yf refrigerant, a standard in newer vehicles due to environmental regulations. This hydrofluoroolefin (HFO) refrigerant has a significantly lower Global Warming Potential (GWP) compared to its predecessor, R-134a. The transition to R-1234yf, which began around 2014 for many manufacturers, was driven by EPA mandates to reduce the environmental impact of automotive air conditioning systems.

While good for the planet, R-1234yf comes with a higher price tag. It also requires specialized equipment for recovery, recycling, and recharging. Standard R-134a recovery machines are not compatible with R-1234yf, making professional service essential for proper handling and to avoid cross-contamination.

Recharge procedure

Recharging your 2020 Chevrolet Silverado 3500HD's A/C system is not as simple as adding a can of refrigerant. An accurate charge is crucial for proper system operation and longevity. Here's a high-level overview of the professional recharge procedure:

1. System Evacuation: The system must first be evacuated using a vacuum pump to remove all air and moisture. Moisture in an A/C system can lead to corrosion and component failure.
2. Leak Test: After evacuation, a vacuum decay test or a refrigerant leak detector is used to confirm the system is leak-free.
3. Accurate Charge by Weight: The correct amount of R-1234yf refrigerant must be added by weight (22 oz or 624 grams) using a specialized A/C charging machine. Do not rely on pressure gauges alone, as ambient temperature and humidity can inaccurately influence readings. An undercharged or overcharged system can lead to reduced cooling performance and premature compressor failure.
4. PAG Oil: Ensure the correct type (PAG 46) and amount (6.75 fl oz or 200 mL) of PAG oil is in the system. When replacing components, it