AMSOIL Signature Series 5W-30 100% Synthetic Motor Oil

The 25,000-mile interval is AMSOIL's label claim for normal (non-severe) service. Community UOA data from BITOG (Bob Is The Oil Guy) forum threads consistently shows healthy TBN and low oxidation markers at 12,000–15,000 miles on typical daily-driver use, with several documented runs past 20,000 miles on highway-dominant driving. The oil is genuinely capable past 10,000 miles; the full 25,000 figure is achievable under favorable conditions but is not the median real-world result. AMSOIL recommends following the OEM drain interval for severe service.

Yes — AMSOIL lists GM dexos1 Gen 3 among the OEM approvals on the Signature Series product page. dexos1 Gen 3 is the current approval required for 2020+ GM gasoline vehicles. The product also lists Ford WSS-M2C946-B1, Stellantis MS-6395, and Honda HTO-06 approvals. Confirm the current OEM approval list on AMSOIL's product page before relying on this oil for warranty documentation.

API SP is the current top-tier gasoline engine oil specification through 2026, succeeding API SN Plus. ILSAC GF-6A adds fuel economy and chain-wear protection on top of API SP — required for most 2020+ gasoline passenger vehicles from Toyota, Honda, Ford, and GM. Using API SP + ILSAC GF-6A oil provides the deposit control, oxidation stability, and LSPI (low-speed pre-ignition) protection that older specs (API SN, SM) may not fully deliver for turbocharged or GDI engines.

Yes. SDS §3 confirms a base stock of Dec-1-ene homopolymer (PAO Group IV, 10–30%) and hydrogenated base oil (Group III, 10–30%) — a Group III + Group IV synthetic blend within the formulation, both classified as full synthetic under API base stock definitions. There is no Group I or Group II conventional content disclosed.

AMSOIL lists Honda/Acura HTO-06 among the approvals for Signature Series 5W-30. Honda Genuine Motor Oil is Honda's private-label product; any oil meeting the HTO-06 spec is functionally equivalent for warranty purposes in engines specifying a 5W-30 viscosity grade. HTO-06 on the 5W-30 grade does not substitute for applications requiring 0W-20 — viscosity-grade match is still required.