Automotive A/C Refrigerants vs. ILSAC Standards
Comparing 2 standards across 14 specifications. 14 key differences identified.
Automotive air conditioning refrigerants are standardized under SAE J639, SAE J2842, and EPA regulations into R-12 (CFC-12 legacy), R-134a (HFC-134a standard since 1994), and R-1234yf (HFO ultra-low GWP standard on modern vehicles), each featuring unique quick-connect service port dimensions and dedicated synthetic compressor oils (PAG vs POE).
ILSAC GF-6 (developed by the International Lubricant Standardization and Approval Committee of Japanese and American automakers) defines fuel economy, timing chain wear reduction, and engine durability standards. Splitting into GF-6A (backward-compatible for 0W-20, 5W-20, 5W-30, 10W-30) and GF-6B (dedicated to ultra-low viscosity 0W-16 oils).
Specification Comparison Table
14 Parameters| Parameter / Spec | ||
|---|---|---|
|
Governing Standards
|
SAE J639 / SAE J2842 / ASHRAE 34 (Refrigerant Safety) / EPA SNAP Program | — |
|
R-12 (Dichlorodifluoromethane)
|
Global Warming Potential (GWP): 10,900 | Ozone Depletion Potential (ODP): 1.0 | 7/16" threaded flare ports | Mineral oil | — |
|
R-134a (1,1,1,2-Tetrafluoroethane)
|
GWP: 1,430 | ODP: 0.0 | High-side 16 mm / Low-side 13 mm quick-connect ports | PAG 46/100/150 oil | — |
|
R-1234yf (2,3,3,3-Tetrafluoropropene)
|
GWP: < 1.0 | ODP: 0.0 | High-side 17 mm / Low-side 14 mm left-hand keyed ports | PAG/POE specialized oils | — |
|
R-744 (Carbon Dioxide / CO2)
|
GWP: 1.0 | Transcritical system operating at ultra-high pressures up to 130 bar (1,885 psi) | Mercedes S-Class option | — |
|
Standard Low-Side Operating Pressure
|
25 to 45 psi (1.7 to 3.1 bar) at 21°C–32°C (70°F–90°F) ambient | — |
|
Standard High-Side Operating Pressure
|
150 to 250 psi (10.3 to 17.2 bar) depending on ambient condenser airflow | — |
|
Oil Compatibility Rule
|
Never use mineral oil with R-134a/R-1234yf; PAG oil is strictly hygroscopic (absorbs atmospheric moisture rapidly) | — |
|
Standardization
|
— | ILSAC GF-6A / ILSAC GF-6B (Mandated May 2020) |
|
ILSAC GF-6A (Starburst Symbol)
|
— | Backward compatible with older GF-5 and GF-4 specifications for SAE 0W-20, 5W-20, 0W-30, 5W-30, 10W-30 |
|
ILSAC GF-6B (Shield Symbol)
|
— | Exclusively for SAE 0W-16 viscosity oils (NOT backward compatible with engines requiring GF-6A / GF-5) |
|
Timing Chain Wear Test (Sequence X)
|
— | A mandatory ASTM test that limits acceptable timing chain elongation over an extended multi-day cyclic engine run (specific pass/fail thresholds are set by the ASTM Sequence X test procedure, not reproduced here in full) |
|
Piston Deposit & Cleanliness (Sequence IIIH)
|
— | A high-temperature ASTM oxidation/deposit test that runs the oil under sustained elevated temperature to evaluate resistance to ring sticking and varnish formation (exact duration/temperature are set by the ASTM Sequence IIIH test procedure) |
|
Automaker Backing
|
— | Alliance of Automobile Manufacturers (Ford, GM, Stellantis) and Japan Automobile Manufacturers Association (Toyota, Honda, Nissan) |