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GUARDOL XT® FULL SYNTHETIC DIESEL ENGINE OIL

PREMIUM FULL-SYNTHETIC API CK-4 DIESEL ENGINE OIL; FORTIFIED WITH LIQUID TITANIUM® PROTECTION ADDITIVE

Phillips 66® Guardol XT Full Synthetic Diesel Engine Oil is a premium full-synthetic oil designed for four-stroke diesel engines operating under severe conditions or extreme temperatures. It meets API CK-4 performance standards for modern low-emission engines built to comply with 2007 and later EPA on-highway emissions regulations and is backward serviceable for older diesel engines. This oil is fully compatible with exhaust aftertreatment systems, including diesel particulate filters, diesel oxidation catalysts, and selective catalytic reduction.

The advanced full-synthetic formulation ensures excellent low-temperature performance, making it ideal for harsh winter climates. Guardol XT is made with synthetic base stocks and a low-SAPS additive package, offering exceptional wear protection, soot control, and bearing corrosion resistance in both conventional and EGR-equipped engines. Its superior soot dispersancy prevents abrasive wear, minimizes oil thickening, and maintains good low-temperature pumpability, even in highly soot-laden oil. Additionally, it provides enhanced oxidation resistance and thermal stability at high temperatures compared to conventional or synthetic blend oils.

Guardol XT meets or exceeds API CK-4 and SN requirements and is approved under the latest OEM specifications for low-emission diesel engines. It is also backward serviceable for earlier API "C" category oils and OEM specifications. Designed for use with diesel fuels containing up to 500 ppm sulfur, it supports ultra-low-sulfur diesel (ULSD) applications. For engines running on higher-sulfur fuels, consult the manufacturer for recommended service intervals.

GUARDOL XT® FULL SYNTHETIC DIESEL ENGINE OIL

Features & Benefits

  • Excellent protection for newer low-emission diesel engines and older diesel engines
  • Specially formulated to protect exhaust aftertreatment systems
  • Outstanding soot control for protection against abrasive wear and soot-induced oil thickening
  • Outstanding resistance to viscosity and thermal breakdown at high temperatures
  • Exclusive Liquid Titanium additive provides enhanced oxidation and wear control
  • Protects against rust, bearing corrosion, and wear
  • Excellent low-temperature pumpability for easier starting and less wear during cold starts
  • High shear stability
  • High resistance to foaming and aeration

Applications

  • On- and off-highway diesel equipment operating at low ambient temperatures
  • On-highway diesel trucks equipped with EGR and exhaust aftertreatment systems to meet 2007/2010 emissions standards
  • Older diesel equipment with conventional, non-EGR engines, or ACERT engines
  • Off-highway construction, earth moving, and mining equipment
  • Mixed fleets with diesel and gasoline-fueled vehicles

Technical Details

Licenses & Approvals:

Guardol XT Full Synthetic Diesel Engine Oil is licensed or meets requirements of:
  • API Service CK-4, CJ-4, CI-4 PLUS, SN
  • Cummins CES 20086
  • Detroit Diesel DFS 93K222
  • Deutz DQC III-10
  • Mack EOS 4.5, Volvo VDS 4.5
  • Mercedes-Benz Sheet 228.31
  • Renault VI RLD-4
  • Ford WSS-M2C171-F1
  • ACEA E9-08, E7-08
  • Caterpillar ECF-3, ECF-2, ECF-1-a
  • Diesel engines manufactured by OEMs not listed above, where the OEM specifies API CK-4 engine oil

Additional Details:

SAE Grade 0W-40
Specific Gravity @ 60°F 0.846
Density, lbs/gal @ 60°F 7.04
Color, ASTM D1500 4.0
Flash Point (COC), °C (°F) 226 (439)
Pour Point, °C (°F) -58 (-72)
Viscosity, Kinematic
cSt @ 40°C 85
cSt @ 100°C 14.4
Viscosity Index 178
Cold Cranking Viscosity, cP @ (°C) 5853 (-35)
High-Temp/High-Shear Viscosity, cP @ 150°C 4.0
Sulfated Ash, ASTM D874, wt % 1.0
Total Base Number (TBN), ASTM D2896 10.8
Titanium 0.010
Zinc, wt % 0.1215

Licenses & Approvals:

Guardol XT Full Synthetic Diesel Engine Oil is licensed or meets requirements of:
  • API Service CK-4, CJ-4, CI-4 PLUS, SN
  • Cummins CES 20086
  • Detroit Diesel DFS 93K222
  • Deutz DQC III-10
  • Mack EOS 4.5, Volvo VDS 4.5
  • Mercedes-Benz Sheet 228.31
  • Renault VI RLD-4
  • Ford WSS-M2C171-F1
  • ACEA E9-08, E7-08
  • Caterpillar ECF-3, ECF-2, ECF-1-a
  • Diesel engines manufactured by OEMs not listed above, where the OEM specifies API CK-4 engine oil

Additional Details:

SAE Grade 5W-40
Specific Gravity @ 60°F 0.855
Density, lbs/gal @ 60°F 7.12
Color, ASTM D1500 4.0
Flash Point (COC), °C (°F) 240 (464)
Pour Point, °C (°F) -48 (-54)
Viscosity, Kinematic
cSt @ 40°C 96.0
cSt @ 100°C 14.5
Viscosity Index 166
Cold Cranking Viscosity, cP @ (°C) 6,230 (-30)
High-Temp/High-Shear Viscosity, cP @ 150°C 4.2
Sulfated Ash, ASTM D874, wt % 1.0
Total Base Number (TBN), ASTM D2896 10.2
Titanium 0.010
Zinc, wt % 0.1288

Licenses & Approvals:

Guardol XT Full Synthetic Diesel Engine Oil is licensed or meets requirements of:
  • API Service CK-4, CJ-4, CI-4 PLUS, SN
  • Cummins CES 20086
  • Detroit Diesel DFS 93K222
  • Deutz DQC III-10
  • Mack EOS 4.5, Volvo VDS 4.5
  • Mercedes-Benz Sheet 228.31
  • Renault VI RLD-4
  • Ford WSS-M2C171-F1
  • ACEA E9-08, E7-08
  • Caterpillar ECF-3, ECF-2, ECF-1-a
  • Diesel engines manufactured by OEMs not listed above, where the OEM specifies API CK-4 engine oil

Additional Details:

SAE Grade 15W-40
Specific Gravity @ 60°F 0.854
Density, lbs/gal @ 60°F 7.20
Color, ASTM D1500 3.5
Flash Point (COC), °C (°F) 233 (451)
Pour Point, °C (°F) -42 (-44)
Viscosity, Kinematic
cSt @ 40°C 104
cSt @ 100°C 14.8
Viscosity Index 148
Cold Cranking Viscosity, cP @ (°C) 4,116 (-20)
High-Temp/High-Shear Viscosity, cP @ 150°C 4.3
Sulfated Ash, ASTM D874, wt % 1.0
Total Base Number (TBN), ASTM D2896 10.3
Titanium 0.010
Zinc, wt % 0.1320