HKS engine oils are developed with an idea of that oil is a tuning part to maximize performance of engine. The unique viscosity categorization will effect at molecular level on boundary lubrication. Optimized oil viscosity selection solves hydrodynamic lubrication. Airtightness and friction are highly balanced. HKS as an engine building specialist now offers 100% synthetic special blend oil.

OIL SERIES Premium Pro Premium Pro RACING PRO RACING PRO RACING PRO HR(-4W31) HR(0W42) EVO-X(3.5W37) 4G63(5.5W38) EJ(7.5W42) 13BT(10W45) JZ-G(10W50) RB(15W55) SUPER OIL Premium0w20 SUPER OIL Premium0w25 SUPER OIL Premium5w30 SUPER OIL Premium7.5w35 SUPER OIL Premium10w40 SUPER OIL Premium7.5w45 SUPER OIL Premium7.5w55 SUPER OIL Premium Deasel5w30 SUPER OIL Premium Deasel7.5w33 SUPER OIL Premium Deasel7.5w44

Description of Viscosity

Description of Viscosity more information

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GEAR OIL G series




Features of HKS Oil Series

Trust Us With Your Engine
  • ・The engine performance can be maximized by the optimized velocity exclusively selected for each purpose of use.
  • ・High performance and oil film maintenance in the range at high speed and temperature require severe viscosity characteristics.
  • ・High driving performance and durability for street to sports driving.

Necessity of Oil Change

Engine oil is usually used for lubrication of internal combustion engines. The main function of engine oil is lubrication, but also sealing, cooling, cleaning, inhibiting corrosion are other important factors. If one of these factors is lacked by engine oil degradation, the engine malfunction, power loss, fuel economy deterioration are caused leading in the worst case to the engine damage.
To always maintain the normal condition of an engine, regular oil change is required.

5 Main Roles of Engine Oil

5 Main Roles of Engine Oil

1 Lubrication → Better lubrication suppresses abrasion of the metal part.

The film made on the roughened fine surface of the metal part covers the engine parts moves in high speed and suppresses abrasion of the metal surface.
Also, suppressing of the metal abrasion and damage prevents the engine output reduction and improves the fuel-saving performance.

2 Sealing → Prevention of compression pressure loss.

The combustion chamber is sealed by the oil entered into the gap between the piston and cylinder; therefore, the mixed air compression efficiency and fuel efficiency are improved, and the combustion gas leakage is prevented, which enable to prevent the engine output reduction.

3 Cooling → Prevention of seizure & damage

Oil circulation removes the heat generated in the engine, and the heat accumulated in the oil is cooled down by an oil cooler and/or oil pan.
Mainly, applying oil to the back of pistons prevents the piston seizure and damage. (The cylinder is cooled by LLC.)

4 Cleaning → Flushing and dispersing sludge and deposit

The oil flushes and disperses sludge and deposit as it circulates inside the engine to prevent substances exerting adverse effect on the engine from being piled up on the pistons and/or ring grooves. ( Deposit is made when applying a temperature to sludge, and deposit becomes carbon after a while.)

5 Inhibiting Corrosion → Prevention of metal corrosion

Neutralizing the acidic substance in the engine and making protection file on the metal part’s surface protect the engine internal from moisture, air, and/or acidic substance to prevent the metal corrosion and rust.

HKS Oil Viscosities Recommended for Normal to Lightly Tuned Engines

  • <Hybrid Car/Eco-car>
    0W-25 - Good fuel efficiency and acceleration response⦆with the low viscosity and high flowability.
  • <Mini Van>
    0W-25-7.5W-55 - Select oil which viscosity is appropriate for the purpose of using a car such as cruising with many passengers, traveling on a high way, etc.
  • <Sports Car>
    7.5w-45 or 7.5W-55 The proper maintenance of the oil film is required for a powerful engine that can run to the high speed range.
  • <Kei-Car>
    0W-25 for high fuel efficiency, 7.5W-45 for turbocharged engines.

HKS Oil Viscosities Recommended for Hard Tuned Engines

Typical Application

  • ・High Power Turbo Engines (RB26, 2JZ, etc) : Racing Pro「 10W50」 ※
  • ・3.5L NA Engines (Toyota GR, Nissan VQ, etc) : HR「 -4W31」
  • ・Sports VTEC Engines (Honda F20C, F22C, B18, etc) : HR「 0W42」
  • ・Cars with HKS GT Supercharger (ZN6/ZC6, etc) : HR「 0W42」 ( high response and high viscosity )
  • ・The Latest High Mechanic NA Engines : Racing Pro「 -5W30」 ※
  • ・Ultimate Custom-made Oil Viscosity : Premium Pro「 0W20「」20W60」 Special Blend
    (For the viscosity change, refer the mixture viscosity table.
    For details, click here.) ※
  • ※Available Only from HKS Authorized Shops

To be Discontinued.