# item.guide
Side-by-Side Comparison Engine Oil & Fluids

ACEA Oil Sequences vs. Engine Coolant & Antifreeze

Comparing 2 standards across 12 specifications. 12 key differences identified.

Comparing:
ACEA Oil Sequences
Engine Coolant & Antifreeze

The European Automobile Manufacturers’ Association (ACEA) Oil Sequences establish stringent oil performance specifications tailored to European driving conditions and exhaust aftertreatment devices. Dividing into A/B Sequences (High-SAPS for older passenger cars without particulate filters) and C Sequences (C2, C3, C5, C6 Low/Mid-SAPS for DPF diesel and GPF gasoline particulate filters).

View full ACEA Oil Sequences spec sheet →

Automotive Engine Coolant (standardized under ASTM D3306 and SAE J1034) consists of an ethylene glycol (or propylene glycol) base mixed 50/50 with demineralized water and specialized corrosion inhibitor additive packages. Dividing into classical IAT (Inorganic Acid), modern OAT (Organic Acid Technology / Long Life), and HOAT (Hybrid OAT with silicates/phosphates).

View full Engine Coolant & Antifreeze spec sheet →

Specification Comparison Table

12 Parameters
Parameter / Spec
Standardization
ACEA Oil Sequences (A/B for standard engines, C for catalyst-compatible, E for heavy-duty commercial diesel)
SAPS Definition
Sulfated Ash, Phosphorus, and Sulfur additives (ZDP anti-wear agents and metallic detergents)
ACEA A3/B4 (High SAPS)
High performance/stay-in-grade stable oil for high-revving European engines; HTHS ≥ 3.5 mPa·s (BMW LL-01, MB 229.5, VW 502.00)
ACEA A5/B5 (High SAPS, Low Friction)
Low-viscosity fuel economy oil with HTHS 2.9 to 3.5 mPa·s (Ford WSS-M2C913-D, Volvo)
ACEA C3 (Mid SAPS, High HTHS)
The European DPF/GPF gold standard: HTHS ≥ 3.5 mPa·s, Sulfated Ash ≤ 0.8% (BMW LL-04, MB 229.51/229.52, VW 504.00/507.00, Porsche C30)
ACEA C5 & C6 (Low SAPS, Low HTHS)
Ultra-low viscosity (0W-20) for modern fuel economy: HTHS 2.6 to 2.9 mPa·s with LSPI protection (BMW LL-17 FE+, VW 508.00/509.00)
Base Liquid Mixture
50/50 mix of Ethylene Glycol and pure demineralized water (Freeze point: -37°C / -34°F; Boil point: 108°C / 226°F at 1 atm, 129°C / 265°F under 15 psi cap)
IAT (Inorganic Acid Technology — Green)
Silicate and phosphate inhibitors (2-year / 30,000-mile service life; standard on pre-2000 vehicles with cast-iron blocks and copper radiators)
OAT (Organic Acid Technology — Orange/Pink)
Carboxylate-based inhibitors (5-year / 150,000-mile long-life; GM Dex-Cool, VW G12/G12+, Toyota Super Long Life, Ford Orange)
Si-OAT / HOAT (Hybrid OAT — Violet/Blue/Yellow)
Combines organic acids with low-depletion silicates or phosphates (VW G13/G12evo, Mercedes MB 325.5, BMW Blue/Magenta, Asian P-HOAT)
Asian P-HOAT (Phosphated HOAT — Pink/Blue)
Uses phosphates instead of silicates (Toyota, Honda, Nissan, Subaru, Hyundai/Kia strictly forbid silicates due to water pump seal erosion)
European Si-HOAT (Silicated HOAT)
Uses silicates instead of phosphates (European water has high calcium hardness; phosphates create calcium phosphate scale deposits)