EVIL ENERGY AN6 Male to 1/4" NPSM Transmission Cooler Adapter — Black 2pcs CNC 6061-T6

EVIL ENERGY AN6 male to 1/4" NPSM transmission cooler adapter — a two-piece, CNC-machined 6061-T6 aluminum fitting set engineered to adapt AN6 lines to legacy 1/4" NPSM transmission cooler ports.

If you need to connect modern AN6 braided lines or aftermarket hoses to older transmission cooler ports, these compact adapters provide a reliable transition. Machined from aircraft-grade 6061-T6 billet aluminum and finished in a protective black coating, the pair is built for corrosion resistance and lightweight strength. They suit a range of automotive fluids and were designed with common transmission models in mind.

How does this adapter let me use AN6 lines on older transmission ports?

These adapters convert an AN6 (9/16-18 UNF male flare) thread to a 1/4"-18 NPSM port, allowing modern AN fittings and braided hoses to mate with factory-style transmission cooler openings. Installation is straightforward: thread the adapter into the transmission port, then attach the AN6 hose end.

• Converts AN6 male flare to 1/4"-18 NPSM female port.
• Works with standard AN6 hoses and braided line assemblies.
• Simple hand-tighten with a wrench on the hexhead; no special tools required.

Which vehicles and transmissions are compatible with these fittings?

The adapter set was created for transmissions and cooler ports found on many pre-2007 vehicles. It lists compatibility with popular transmissions used in classic and late-model GM and other makes, making it useful when retrofitting aftermarket coolers or custom plumbing.

• Commonly fits TH350, TH400 and 700R4 transmission cooler ports.
• Also compatible with 4L60E, 200-4R, TR6060, AOD, 4R100, 4R70W and C5 applications.
• Designed for front and rear transmission line ports on older vehicles.

What materials and manufacturing features ensure durability?

Each adapter is CNC-machined from 6061-T6 billet aluminum for consistent dimensions and a strong, lightweight part. The black finish improves corrosion resistance while the hex head design speeds installation and removal without damaging the fitting.

• 6061-T6 billet aluminum for high strength-to-weight ratio.
• CNC machining ensures precise threads and sealing surfaces.
• Black protective coating reduces rust and environmental wear.

Which fluids and environments are these adapters suitable for?

These fittings are compatible with common automotive fluids — including transmission fluid, engine oil, and fuel — when used with appropriate hoses and seals. They are not a substitute for the correct hose/adapter sealing methods; always use compatible seals and verify thread engagement.

• Compatible with transmission fluid, oil, fuel and coolant lines when used properly.
• Works with AN6 hose assemblies and standard NPSM ports when sealed correctly.
• Sold as a 2-piece set to equip both supply and return cooler lines if needed.

Who is this for: This adapter set suits mechanics, hot-rodders and DIY auto enthusiasts who are upgrading or repairing transmission cooler plumbing on older vehicles. If you’re converting factory cooler ports to modern AN6 lines for improved hose options, routing flexibility, or aftermarket cooler installations, these compact, machined aluminum fittings provide a durable and affordable solution. They’re especially helpful on classic GM transmissions (TH350/TH400/700R4/4L60E) and many late-model swaps where AN connections are preferred.

• Included: Two (2) AN6 male to 1/4"-18 NPSM adapters.
• Material: 6061-T6 billet aluminum, black finish.
• Installation: Thread into 1/4" NPSM port, tighten hex head, attach AN6 hose.
• Use cases: Transmission cooler retrofit, custom plumbing, aftermarket cooler installations.