We cite primary and standards-body sources, and treat owner's manuals as the final authority for any specific vehicle. Below are the references behind our explanations.
Standards bodies & specifications
- SAE International — the J300 viscosity-grade standard (what 5W-30, 0W-20 etc. mean).
- API (American Petroleum Institute) — service categories such as API SQ and API SP.
- ILSAC — fuel-economy oil standards such as GF-7A / GF-7B and GF-6A / GF-6B.
- ACEA — European oil sequences (A/B, C, etc.).
- OEM approvals — manufacturer specs such as GM dexos, VW 504.00/507.00, BMW Longlife, Mercedes-Benz MB-Approvals.
Vehicle-specific data
Car recommendations are built from owner's manuals and OEM maintenance information, then
cross-checked against manufacturer material, licensed datasets, and retailer/product data.
Each row carries sourceTier, structured sources[] provenance, confidence,
market, manual version, and a last-verified date. See our
methodology for exactly how sources are weighted, the
owner's manual finder for official OEM manual portals,
and the current freshness dashboard at /freshness. The raw
deterministic manifest is published at
/content-freshness.json.
Measurement hooks
Search, correction, and vehicle-lookup flows emit local analytics events so launch-day measurement can be connected without changing the UX. The noindexed analytics event catalog lists the current event names, fields, and debug mode.
Operational surfaces
The internal operations hub links the freshness dashboard, analytics catalog, correction intake, review queue, launch checklist, generated manifests, and launch/runbook documents.
Import readiness
Future vehicle rows can be staged from the CSV template in the project docs and imported into JSON with the local importer. Imported rows remain low-confidence unless they include primary OEM source evidence; the validation gate blocks medium/high confidence rows without that evidence.
The owner's manual is final
Nothing here replaces the manual for your exact year, make, model, engine, and market. Always confirm there; the manual finder lists official brand portals to start from.
Report a correction
Spotted an error or an out-of-date spec? Use the "Report a correction" link on a car page. It pre-fills the page URL, vehicle, current source, confidence, and status. Please add the manual page or OEM source you are citing. The hosted endpoint scaffold stores structured submissions when deployed; the email fallback remains available for local/static previews.