Archoil AR6500 Diesel Treatment

AR6500 combines a strong cetane boost with injector cleaning and lubricity protection in a single every-tank treatment. The cetane improver is confirmed from the reference SDS, and the brand states it delivers up to 8 cetane points — though no independent test result backs that claim. The detergent and lubricity actives are undisclosed. Community reception is overwhelmingly positive: 4.8 out of 5 across 166 Amazon ratings with particular enthusiasm from Ford 7.3L and 6.0L Powerstroke owners who report smoother idle and improved cold-start response. The treat rate is 1 oz per 10 gallons, dosed at every fill-up. One recurring complaint: the bottle redesign removed the attached dosing hose, forcing owners to use a separate funnel.

Best for Powerstroke and other diesel truck owners running non-Top-Tier fuel who want a combined cetane and cleaning treatment with strong community credibility. Skip it if the undisclosed detergent and lubricity chemistry is a dealbreaker — products with named PEA detergent actives and published HFRR wear-scar data provide more verifiable value.

The reference SDS carries WARNING from H302 (harmful if swallowed) and H332 (harmful if inhaled), both driven by the 2-EHN cetane improver concentration. H315 skin irritation and H319 eye irritation from aromatic hydrocarbon carriers. The concentrate pour at the diesel tank fill neck is the primary exposure window — H332 inhalation classification means the vapor exposure during a 15-45 second pour is the limiting risk, particularly in enclosed spaces. High-VOC concentrate (estimated >550 g/L) with H412 aquatic toxicity from the 2-EHN fraction. All health and environment scores are based on the sibling AR6900-D MAX SDS — partial confidence applies.