2018 Ram 2500 A/C Refrigerant & Oil Capacity Guide

Quick Answer

• Refrigerant Type: R-1234yf
• Full System Charge: 22 oz (624 grams)
• PAG Oil Type: PAG 46
• PAG Oil Amount: 7.1 oz (210 mL)
• Low-Side Service Port Location: On the accumulator, near the firewall on the passenger side.
• High-Side Service Port Location: On the liquid line, typically near the condenser at the front of the vehicle on the passenger side.

Why R-1234yf Matters

For your 2018 Ram 2500, the air conditioning system uses R-1234yf refrigerant. This is a significant change from the older R-134a refrigerant found in vehicles prior to approximately 2014. The transition to R-1234yf was driven by environmental concerns, as it has a much lower Global Warming Potential (GWP) compared to R-134a. This means it contributes far less to climate change if released into the atmosphere.

While R-1234yf is more environmentally friendly, it also comes with some implications. You'll notice that the cost of R-1234yf refrigerant is higher than R-134a. Additionally, specialized equipment is required for its recovery and recharging. Standard R-134a recovery machines cannot be used with R-1234yf due to different fitting sizes and the need for stricter purity standards. This is why it's crucial to take your vehicle to a facility equipped for R-1234yf service.

Recharge Procedure Cautions

Recharging an R-1234yf A/C system is not as simple as adding a can of refrigerant. It requires precision and adherence to specific procedures. Never attempt to recharge your A/C system by pressure readings alone or by simply "topping off" with refrigerant. The only correct way to charge an A/C system is by weight, using a precise electronic scale and dedicated R-1234yf service equipment.

Before adding any refrigerant, the system should be evacuated using a vacuum pump to remove any air and moisture. Air and moisture in the A/C system can lead to corrosion, poor cooling performance, and premature component failure. After evacuation, the system should hold a vacuum, indicating no significant leaks. Only then should the specified amount of R-1234yf refrigerant and PAG 46 oil be charged into the system by weight.

Safety Disclaimer: Working with automotive air conditioning systems involves high pressures and specialized refrigerants. Improper handling can lead to serious injury and environmental damage. Federal law (EPA Section 609) requires anyone servicing mobile air conditioning systems to be certified. It is strongly recommended that A/C system service be performed by a certified professional.

Common A/C Problems for the 2018 Ram 2500

While the Ram 2500 is a robust truck, its A/C system can experience common issues similar to other vehicles. Some frequent problems include:

• Compressor Failures: The A/C compressor is the heart of the system. Failures can manifest as a lack of cold air, grinding noises from the engine bay when the A/C is on, or a seized clutch. Proper system maintenance, including correct refrigerant and oil levels, can help prolong compressor life.
• Condenser Issues: Located at the front of the vehicle, the condenser is susceptible to damage from road debris. A damaged condenser can leak refrigerant, leading to a loss of cooling. Blocked fins from dirt and debris can also hinder its ability to dissipate heat, reducing efficiency.
• Evaporator Leaks: The evaporator is located inside the dashboard. Leaks here are less common but can be very challenging to diagnose and repair as they often require significant dashboard disassembly. Signs include a musty odor from the vents (due to refrigerant oil mixing with moisture) and a gradual loss of cooling.
• Blend Door Actuator Failures: While not directly a refrigerant problem, a failed blend door actuator can prevent proper air distribution or temperature control, making it seem like the A/C isn't working correctly. You might hear clicking noises from behind the dash or experience air blowing only hot or only cold.

When to Call a Pro

If you're experiencing any A/C problems with your 2018 Ram 2500, especially a lack of cold air, unusual noises, or a noticeable smell, it's best to consult a professional. Given the complexity of R-1234yf systems and the necessity of specialized equipment, an EPA 609 certified technician is best equipped to properly diagnose and repair the issue, ensuring your system operates efficiently and reliably.

Find a certified A/C shop on Repairius.