Metric EFI Adapter Kit – M14x1.5 & M16x1.5 to AN6 for OBS, GMT400 Blazer & Suburban Sending Units

Upgrade your fuel system the right way with our Metric EFI Adapter Fitting Kit, specifically designed for OBS (Old Body Style) GMT400 Blazer and Suburban EFI sending units. This all-in-one kit includes the exact metric fittings needed to convert your factory fuel sender ports to AN6 — no cutting, flaring, or modifying required.

Whether you're swapping in an LS engine or modernizing your EFI plumbing, this adapter kit bridges the gap between OEM hard lines and high-performance AN fuel hose systems.

✅ Kit Includes:

• 1x M14x1.5 to AN6 Adapter Fitting – for return line
• 1x M16x1.5 to AN6 Adapter Fitting – for feed line

Everything you need to convert your OBS or GMT400 sending unit to AN plumbing in one convenient kit.

🧰 Compatible With:

This kit threads directly into the sending units found in 1987–1991 OBS and GMT400 Chevy/GMC Blazer and Suburban fuel tanks, converting the factory threaded ports to AN6 male threads for use with modern EFI and LS swap fuel systems.

🔗 Works With These EFI Sending Units:

Choose the correct Spectra Premium EFI sending unit based on your fuel tank size:

• ✅ FG12M – 40 Gallon Tank
• ✅ FG12L – 31 Gallon Tank
• ✅ FG12K – 25 Gallon Tank

💪 Why Choose This Kit?

• 🔧 No guesswork – Threads match OEM ports perfectly
• 🔗 Seamless connection to AN6 hose ends
• 🛠 Built for pressure – Handles EFI demands with ease
• ⛽ Compatible with modern fuels, including ethanol blends and E85

🛠 Installation Tips:

• Apply fuel-safe thread sealant on the metric threads
• Hand-tighten first, then snug gently with a wrench
• Connect your AN6 hose ends to the adapters as normal

🔥 Recommended Pairings:

• PTFE AN Hose & Fittings Bundles »
• LS Swap Fuel System Kits »
• Inline EFI Fuel Filters »

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