2019 Chevrolet Silverado 3500HD A/C Refrigerant & Oil Capacity

Quick Answer

• Refrigerant Type: R-1234yf
• Full System Charge: 22.93 oz (650g)
• PAG Oil Type: PAG 46 (Specific AC Delco P/N 15-70007 or equivalent)
• PAG Oil Amount: 4.7 fl oz (140 mL)
• Low-Side Service Port Location: On the accumulator/drier, near the firewall on the passenger side.
• High-Side Service Port Location: On the liquid line, typically near the condenser on the passenger side, or sometimes closer to the compressor.

Why R-1234yf Matters

The 2019 Chevrolet Silverado 3500HD utilizes R-1234yf refrigerant, a significant change over the older R-134a. This transition, which began around 2014 for many vehicles, was driven by environmental regulations aimed at reducing the global warming potential (GWP) of refrigerants. R-1234yf has a GWP significantly lower than R-134a, making it a more eco-friendly choice.

However, this newer refrigerant comes with its own considerations. R-1234yf is generally more expensive than R-134a. Furthermore, specialized equipment is required for its recovery and recharging. Standard R-134a recovery machines are not compatible with R-1234yf systems due to different fittings and recovery procedures designed to prevent cross-contamination and ensure safety. Shops working with R-1234yf must invest in specific, often more costly, machinery.

Recharge Procedure

Recharging your 2019 Silverado 3500HD's A/C system is not as simple as adding a can of refrigerant. It's crucial to understand that an A/C system is a precisely charged system, and adding refrigerant based solely on pressure readings can lead to overcharging or undercharging, both of which can cause damage and reduce efficiency.

The correct procedure involves:

1. Recovery: Any existing refrigerant in the system should be safely recovered using an EPA-certified R-1234yf recovery machine.
2. Evacuation: The system must then be evacuated with a vacuum pump to remove all air and moisture. Moisture in an A/C system can lead to corrosion and component failure.
3. Leak Testing: Before recharging, the system should be leak-tested to ensure there are no breaches. Even a small leak will cause the system to lose refrigerant over time.
4. Recharge by Weight: The most critical step is to charge the system with the precise amount of refrigerant by weight, as specified above (22.93 oz or 650g). This is typically done with an A/C charging machine that measures the refrigerant accurately.

**Never attempt to charge your A/C system using pressure gauges alone or by