From the premium protection and fuel efficiency of full synthetic to the reliability of conventional, you can count on Guardol to supply the right oil for every machine in your fleet.
Phillips 66® Guardol® Heavy Duty Engine Oils are formulated to extend the life of your equipment and increase fuel economy. Our products exceed all CK-4 and FA-4 specifications while keeping superior wear protection.
FIND THE RIGHT GUARDOL FOR YOUR EQUIPMENT

GUARDOL FE
FULL SYNTHETIC FOR FUEL ECONOMY
API FA-4 5W-30
Applications
On-highway diesel trucks recommending FA-4 to meet 2017 emissions standards, or mixed fleets with diesel and gasoline fueled vehicles.
Key Benefits
- Most aggressive fuel economy savings in our lineup with outstanding wear protection
- High shear stability
- Specially formulated to protect exhaust aftertreatment systems

GUARDOL XT
FULL SYNTHETIC WITH LIQUIDTITANIUM
API CK-4 0W-40, 5W-40
Applications
On-highway diesel trucks, off-highway construction, earth moving and mining equipment, especially those operating at low ambient temperatures or in artic conditions.
Key Benefits
- Outstanding soot control for protection against abrasive wear and soot-induced oil thickening
- Exclusive Liquid Titanium additive provides enhanced oxidation and wear control
- High shear stability and resistance to foaming and aeration

GUARDOL EURO
FULL SYNTHETIC
API CK-4 5W-30, 10W-40
Applications
On- and off- highway diesel equipment operating at low ambient temperatures and those needing to meet certain European specification requirements.
Key Benefits
- Outstanding soot control for protection against abrasive wear and soot-induced oil thickening
- Excellent low-temperature pumpability for easier starting and less wear during cold starts
- MB 228.51 (5W-30); Scania Low Ash (10W-40)

GUARDOL FE
SYNTHETIC BLEND FOR FUEL ECONOMY
API FA-4 10W-30
Applications
On-highway diesel trucks where additional fuel savings are desired.
Key Benefits
- All the durability of Guardol ECT®, but with a lower High-Temperature High-Shear (HTHS) value for increased fuel economy

GUARDOL ECT
SYNTHETIC BLEND
API CK-4 10W-30, 15W-40
Applications
On-highway diesel trucks, off-highway construction, earth moving and mining equipment in severe duty service.
Key Benefits
- Ideal for severe duty service or extended oil drain intervals
- Excellent protection for newer low-emission diesel engines and older diesel engines
- Exclusive Liquid Titanium protection additive provides enhanced oxidation resistance and protection against engine wear

GUARDOL FLEET EC
FOR LOW-EMISSION ENGINES
API CK-4 10W-30, 15W-40
Applications
Specially formulated for compatibility with exhaust aftertreatment systems using diesel particulate filters (DPFs), diesel oxidation catalysts (DOCs) and/or selective catalytic reduction (SCR).
Key Benefits
- Conventional CK-4 oil for moderate duty service
- Protects against particulate filter plugging

GUARDOL ECO
ENVIRONMENTALLY RESPONSIBLE
API CK-4 15W-40
Applications
On-highway diesel trucks off-highway construction, earth moving and mining equipment.
Key Benefits
- Formulated with 100% re-refined base oil
- Ideal for federal, state, county and municipal customers
- Lessens the environmental impact of used oil disposal
- Protects against rust, bearing corrosion and wear

GUARDOL NG-D
FOR MIXED FLEETS
CES 20092, API CK-4/SN 15W-40
Applications
Transit buses, school buses, delivery trucks and other vehicles operating on CNG or natural gas.
Key Benefits
- Excellent wear protection for diesel and gasoline engines, as well as engines converted to natural gas service
- Reduces risk of misapplication in mixed fleets
- High dispersancy protects against sludge and varnish formation
- Protects against valve stem deposits and valve seat recession
HOW MUCH CAN YOU SAVE BY SWITCHING TO GUARDOL FE 10W-30?

CONTACT US TO LEARN MORE
Trying to decide which Guardol formula is right for your equipment? Ready for a trial? Complete this form and a Phillips 66 representative will contact you.
TAKE THE TWO-CHANGE CHALLENGE.
PUT YOUR CURRENT HEAVY DUTY ENGINE OIL TO THE TEST COST AND RISK FREE.
Up for the challenge?