2018 International MV A/C Refrigerant & Oil Specifications

As an ASE-certified HVAC technician, I know that servicing medium-duty trucks like the 2018 International MV requires precise specifications and a solid understanding of heavy-duty climate control systems. Whether you are running a fleet or maintaining an owner-operator rig, keeping the cab cool is essential for driver safety and comfort. Below is your comprehensive A/C refrigerant and oil reference guide for the 2018 International MV.

Disclaimer: Under the Clean Air Act, Section 609, any technician repairing or servicing motor vehicle air conditioning (MVAC) systems for consideration must be EPA 609 certified. Handling refrigerants without proper training and equipment is illegal and environmentally hazardous.

Quick Answer: 2018 International MV A/C Specs

Always verify these capacities against the OEM under-hood A/C decal, as specifications can vary based on specific cab configurations (Day Cab vs. Extended/Crew Cab) and engine options (Cummins B6.7 or L9).

• Refrigerant Type: R-134a (While light-duty vehicles began transitioning to R-1234yf in 2014, most 2018 medium/heavy-duty trucks like the MV retained R-134a. Always check the OEM sticker).
• Full System Charge: Typically 32 oz to 40 oz (907 g to 1134 g) depending on cab size and sleeper/HVAC routing.
• PAG Oil Type: PAG 46 (commonly used with Sanden compressors on these engines).
• PAG Oil Amount: Typically 8 to 10 oz (236 to 295 mL) for a completely flushed system.
• Service Port Locations:
  • Low-Side Port: Located near the accumulator on the passenger side of the firewall/bulkhead.
  • High-Side Port: Typically located on the passenger side, near the A/C compressor or inline toward the condenser.

Why R-1234yf Matters

While your 2018 International MV likely utilizes R-134a, the automotive and trucking industry's 2014+ transition to R-1234yf is critical to understand. The EPA mandated this shift to reduce Global Warming Potential (GWP). R-1234yf has a GWP of less than 1, compared to R-134a’s 1,430.

If you are managing a mixed fleet, you must be aware that R-1234yf is significantly more expensive per pound. Furthermore, it is mildly flammable (classified as A2L) and requires dedicated, specialized recovery and charging machines. You cannot legally or safely cross-contaminate R-134a and R-1234yf equipment.

Recharge Procedure

When servicing the A/C on an International MV, ditch the cheap auto-parts-store "recharge cans" with the built-in gauge. Proper fleet maintenance requires precision.

1. Recover: Recover the existing refrigerant using an EPA-approved R-134a recovery machine.
2. Evacuate: Pull a deep vacuum on the system for a minimum of 30 to 45 minutes to boil off any moisture and check for gross leaks.
3. Charge by Weight, Not Pressure: Ambient temperatures heavily skew pressure readings. The only way to guarantee peak cooling capacity and prevent compressor slugging is to weigh in the exact charge (e.g., 36 oz) using a digital refrigerant scale or automated A/C machine.
4. Verify: Monitor your high and low-side pressures with manifold gauges while verifying center vent temperatures in the cab.

Common A/C Problems for this Vehicle

Medium-duty trucks work hard in tough environments. Over time, you may encounter a few common A/C failures on the International MV generation:

• Condenser Damage: Located right up front, the MV's condenser is highly susceptible to rock strikes, road debris, and bug buildup. A clogged or punctured condenser is a leading cause of poor cooling and high-side pressure spikes.
• Compressor Clutch Failures: With high idle times and constant cycling, the Sanden A/C compressor clutch can wear out prematurely, leading to a system that blows warm air intermittently.
• Evaporator Leaks: Heavy vibrations from the chassis can sometimes stress the HVAC box behind the dash, leading to micro-leaks in the evaporator core over tens of thousands of miles.
• Blower Motor Resistor Issues: If your A/C only works on the highest fan speed, the blower motor resistor has likely failed.

When to Call a Pro

Topping off a slightly low system might seem simple, but A/C systems are closed loops; if you are low on refrigerant, you have a leak that needs repairing. If your A/C compressor has catastrophically failed (sending metal debris through the lines), or if you lack an EPA-approved recovery machine, a manifold gauge set, and a vacuum pump, it is time to step away. Professional shops have the tools to flush the system, replace the accumulator, and accurately weigh in the new charge to keep your MV on the road.

Find a certified A/C shop on Repairius.