Premium Canadian-made BOSS API CK-4 heavy-duty diesel engine oils – choose premium Full Synthetic (true Group III – 0W-40 & 5W-40) for ultimate cold-weather flow, fuel economy, and extended drains in extreme Canadian winters, or Extreme (10W-30 fuel-economy & proven 15W-40) for outstanding soot control, wear protection, oxidation/aeration resistance in high-load, high-soot, mixed fleets. Both lines are low-ash formulations engineered to exceed the latest CK-4 requirements (including new oxidation & aeration tests) for 2010+ EGR / 2017+ GHG engines with DPF/SCR systems while being fully backward compatible with CJ-4/CI-4+ and older specs – perfect for trucking, construction, agriculture, mining, logging, and severe-service diesel engines.

Deliver exceptional piston cleanliness, valve train protection, shear stability, TBN retention, and extended drain capability even under severe operating conditions with high soot loading and fuel sulfur levels.

✅ Key Benefits:

• Exceeds API CK-4 & backward compatible to CJ-4, CI-4+, CI-4, CH-4
• Outstanding soot thickening control & aeration resistance – passes latest CK-4 tests
• Superior wear protection for cams, bearings, cylinder liners & valve train
• Exceptional piston deposit control & engine cleanliness
• High TBN retention for extended drain intervals & acid neutralization
• Excellent oxidation, thermal & shear stability – stays in grade longer
• Low-ash formulation protects DPF, SCR & catalytic converters
• Outstanding cold-start performance & pumpability (especially low-vis grades)
• Proudly formulated and bottled in Canada

✅ Grade-Specific Advantages:

• 0W-40 Full Synthetic → Ultimate arctic cold-start flow (-54°C pour), maximum fuel economy, extended drains in extreme cold fleets
• 5W-40 Full Synthetic → Superior all-season performance, high VI, maximum protection in severe duty & high temperatures
• 10W-30 Extreme → Fuel-economy optimized for modern GHG engines, lower viscosity, excellent soot handling
• 15W-40 Extreme → The #1 heavy-duty workhorse – proven high-soot protection, perfect for mixed fleets & hot climates

Typical Physical Specifications (representative values):

0W-40 Full Synthetic • Kinematic Viscosity @ 40°C: 87.3 cSt • Kinematic Viscosity @ 100°C: 15.1 cSt • Viscosity Index: 180 • CCS @ –35°C: 5360 cP • Pour Point: –54°C • Flash Point: 188°C

5W-40 Full Synthetic • Kinematic Viscosity @ 40°C: 87.8 cSt • Kinematic Viscosity @ 100°C: 14.8 cSt • Viscosity Index: 177 • CCS @ –30°C: 5600 cP • Pour Point: –45°C • Flash Point: 225°C

10W-30 Extreme • Kinematic Viscosity @ 40°C: 81.7 cSt • Kinematic Viscosity @ 100°C: 12.2 cSt • Viscosity Index: 145 • Pour Point: –39°C • Flash Point: 237°C

15W-40 Extreme • Kinematic Viscosity @ 40°C: 113.9 cSt • Kinematic Viscosity @ 100°C: 15.6 cSt • Viscosity Index: 145 • Pour Point: –33°C • Flash Point: 226°C

Meets or Exceeds: • API CK-4, CJ-4, CI-4+, CI-4, CH-4 / SN (5W-40) • Cummins CES 20086, 20081, 20087 • Detroit Diesel DFS 93K222, 93K218, 93K233 • Volvo VDS-4.5, VDS-4, VDS-3 • Mack EOS-4.5, EO-O Premium Plus & earlier • Caterpillar ECF-3, ECF-2 • Mercedes MB 228.31 • MAN M3575 • Ford WSS-M2C171-F1 • Renault RLD-4 • MTU Category 2.1 • ACEA E7 • JASO DH-2 • Suitable for virtually all North American, European & Asian on/off-highway diesel engines requiring CK-4 or earlier specifications

EHC is included in the price

Safety Data Sheet