
VLS closes investigations after Silverhook takes positive action to reformulate engine oils.
The Verification of Lubricant Specifications (UK) Ltd (VLS), an independent and impartial body which investigates lubricant product complaints, has closed investigations VLS 010226 and VLS 010227 after the company involved took corrective action.
In April 2025, VLS received a complaint about Silverhook Ultra-V 0W-30 PCEO. The case concerned the product’s compliance with SAE J300, which specifies that for an SAE 0W-X grade, the Low Temperature Pumping Viscosity (MRV) should be a maximum of 60,000 mPa.s at -40°C with no yield stress. Upon analysis, a sample from the batch was found to have a viscosity of 119,000 mPa.s, and a yield stress of < 210 g was observed. Consequently, the product did not meet the ACEA and API specifications claimed.
In response, Silverhook stated that the issue had been brought to their attention previously by SAIL, the company responsible for the Technical Association of the European Lubricants Industry (ATIEL)’s product compliance monitoring programme. This issue had been resolved with SAIL in line with the guidance set out in European Engine Lubricant Quality Management System (EELQMS) Bulletin 11.
Following testing on some of their engine oils, Silverhook identified that one did not meet MRV at -40°C. They subsequently spoke to their additive suppliers to correct the issue and amended the formulation.
In October 2025, VLS received a complaint regarding Silverhook 0W-20 Fuel Efficient PCEO. The case concerned compliance with SAE J300 and ACEA C5 & C6. VLS testing showed that the sample was compliant for Phosphorous content at 0.0789% but was not compliant for Yield Stress at -40 degrees centigrade, measured at <105g, or Apparent Viscosity at -40 degrees centigrade, measured at 74,200 mPa.s.
In response, Silverhook stated that they had amended the formulation prior to the VLS investigation, which would bring the product back into compliance, and these actions had been agreed with a third party.
Based on the action taken by Silverhook and the assurances given by the third party, VLS was content to close the investigations subject to a standard six-month review.
Darren Frogson, VLS Chairman, said, “We would like to thank Silverhook for their positive, proactive action in this case to address product formulations. As the lubricants sector navigates rapid change in response to OEM design changes and the need to meet increasing emissions legislation, we must have a robust, anonymous process that holds lubricant producers and marketers to account and protects end users.
Workshops must have confidence that the products they select are suitable for use in the application and can deliver what they claim. Our objective is always to bring products into compliance, and we thank Silverhook for taking action to protect end users.”
VLS is an independent organisation that provides a credible and trusted means to verify lubricant specifications, brings transparency to the lubricant marketplace, and protects and educates end users.
You can keep up to date with VLS investigations at their website: https://ukla-vls.org.uk/.
If you have any concerns about a lubricant, you can report them to VLS by calling 01442 875922 or emailing admin@ukla-vls.org.uk.