PCMO Specifications in the Fast Lane

GF-5 Plus: An Eye on LSPI

Original equipment manufacturers (OEMs) have been turning to smaller, turbocharged, gasoline-direct-injection (T-GDI) engines for years to meet increasingly strict fuel-economy and emissions requirements. Although modern T-GDI engines deliver more power while using less fuel and producing fewer harmful emissions than their predecessors, a potentially damaging side effect has emerged: low-speed pre-ignition (LSPI).

LSPI is a more destructive form of regular pre-ignition, which has been around as long as the internal-combustion engine. Because motor oil formulation can play a huge role in combating LSPI, the new ILSAC GF-6 motor oil specification is slated to include a test for LSPI. But the introduction of ILSAC GF-6 has suffered delays and won’t take effect until 2019 at the earliest. OEMs, however, can’t wait that long. For that reason, some are pushing hard for an interim specification to measure LSPI protection.


This pressure has spurred the American Petroleum Institute (API) to fast track API SN Plus and set an optimistic Jan. 1 release date. Similar to the proposed GF-5 Plus, this supplemental specification requires motor oil to meet particular benchmarks that reduce the likelihood of LSPI. General Motors’ proprietary dexos1® Gen 2 specification, released in August, also requires motor oils to undergo an LSPI test. The SN Plus designation, would likely be integrated into the API “donut” and displayed on the back label of motor oil packaging.  

Ahead of the Game

A properly formulated motor oil is critical for protecting an engine against LSPI. As the industry struggles to catchup, AMSOIL has thoroughly examined the threat LSPI poses and has already developed solutions. We’ve developed advanced detergent systems that protect against LSPI and exceed the industry standards. Signature Series, XL and the soon to be released reformulation of OE achieved 100 percent protection against LSPI1 in the engine test required by GM’s dexos1 Gen 2 specification  – zero occurrences were recorded.

You can trust AMSOIL synthetic motor oils to protect your modern T-GDI engine against LSPI and deliver years of reliable service.

1Based on independent testing of AMSOIL Signature Series, XL and OE 5W-30 Motor Oil in the LSPI engine test as required for the GM dexos1 Gen 2 specification.

All trademarked names are the property of their respective owners and may be registered marks in some countries. No affiliation or endorsement claim, express or implied, is made by their use

Refine your search

Filter by

Look Up Guide
Get the Latest News
Connect with AMSOIL
Connect with AMSOIL
Connect with AMSOIL
Two Ways To Save