What Is API SQ Motor Oil? The Latest API Spec

What Is API SQ Motor Oil?

Short answer: API SQ is the newest API gasoline engine-oil service category, the successor to API SP. It's designed for the latest gasoline engines and raises the bar on protection against low-speed pre-ignition (LSPI), timing-chain wear, deposits, and oil oxidation, while supporting fuel economy and emissions-system protection. API SQ is introduced alongside the new ILSAC GF-7 standard (GF-7A and GF-7B).

Where API SQ fits in the API sequence

API gasoline categories advance over time as engines change: SN → SP → SQ. Each new category is meant to protect newer engine technology (turbocharging, direct injection, downsizing, advanced emissions systems) while remaining suitable for many older engines.

What API SQ improves

  • LSPI protection — guards turbocharged, direct-injection engines against damaging low-speed pre-ignition events.
  • Timing-chain wear — maintains protection for modern chain-driven valvetrains.
  • Deposit & sludge control — keeps pistons and engines clean under modern operating conditions.
  • Oxidation stability — supports longer, hotter service.
  • Fuel economy & emissions — works with ILSAC GF-7A to support efficiency and protect catalytic/emissions hardware.

API SQ and ILSAC GF-7A / GF-7B

API SQ is the API service category; ILSAC GF-7 is the companion standard from the auto and oil industries, split into GF-7A (standard viscosity grades) and GF-7B (a low-viscosity subset for fuel economy). Oils meeting GF-7A also meet API SQ.

Is API SQ backward compatible?

A new category is generally designed to be backward compatible, so an API SQ oil can typically be used where API SP, SN, or earlier was recommended — provided you use the correct viscosity grade for your engine. Always match the grade in your owner's manual.

Ultra1Plus API SQ oils

Ultra1Plus offers API SQ motor oils, Made in USA, including ILSAC GF-7A grades:

Looking for an API SQ / GF-7A oil in your grade? Check the spec on the product page or contact our team. Bulk drums and totes available.

Frequently asked questions

What is API SQ motor oil?

API SQ is the newest API gasoline engine-oil service category, succeeding API SP. It's built for the latest gasoline engines with improved protection against LSPI, timing-chain wear, deposits, and oxidation, and supports fuel economy and emissions protection. It's introduced alongside ILSAC GF-7.

What is the difference between API SQ and API SP?

API SQ is the newer category and raises performance requirements for modern engines (LSPI, chain wear, deposits, oxidation, efficiency) beyond API SP. SQ oils are generally suitable where SP was recommended.

Is API SQ the same as ILSAC GF-7A?

They're companion standards. API SQ is the API service category; ILSAC GF-7A is the industry standard for specific viscosity grades. Oils meeting GF-7A also meet API SQ.

Can I use API SQ oil in an older engine?

Yes, in most cases — newer API categories are designed to be backward compatible. Use the viscosity grade specified in your owner's manual.