Aluminum Crush Washer - AN Sizing

Crush washers are single-use by design, which is exactly why the drawer should never run dry.

Banjo bolts, drain plugs, and washer-sealed fittings all seal the same way: a soft aluminum ring crushed once, replaced always. The Finish Line Factory Aluminum Crush Washer in AN-referenced sizing covers ODs of 15.9mm OD, 17mm OD, 20mm OD, 25.3mm OD, 28.28mm OD, 33.5mm OD, 40mm OD, 47.5mm OD with IDs of 9.8mm ID, 11.3mm ID, 14.5mm ID, 19.3mm ID, 22.5mm ID, 27.2mm ID, 33.5mm ID, 41.5mm ID. Refer to the size chart, buy in handfuls, and never reuse the old one.

Benefits

• Washer-sealed joints stop weeping after service, every time
• The crush is a felt event: the washer gives, the torque settles, the joint is done
• A stocked assortment ends the oil-change-delayed-by-one-washer problem
• Banjo rebuilds proceed without cannibalizing old, work-hardened rings

Features

• Soft aluminum construction, designed to crush and conform once
• AN-referenced sizing: ODs 15.9mm OD, 17mm OD, 20mm OD, 25.3mm OD, 28.28mm OD, 33.5mm OD, 40mm OD, 47.5mm OD
• IDs: 9.8mm ID, 11.3mm ID, 14.5mm ID, 19.3mm ID, 22.5mm ID, 27.2mm ID, 33.5mm ID, 41.5mm ID
• For banjo fittings, magnetic drain plugs, and washer-sealed hardware
• Sold individually; stock multiples

The Details

A crush washer seals by sacrifice: soft aluminum flows into the microscopic texture of both faces under torque, conforming perfectly exactly once. Reused, it presents work-hardened metal in the old shape and seals against nothing, which is why every credible service manual says replace, not inspect. Faces must be clean and flat, torque must crush without stretching the bolt, and on stacked banjo joints every interface gets its own fresh ring. Sizing runs on ID first, clearing the bolt or plug shank, with OD covering the sealing face; the AN-referenced range here matches AN-adjacent hardware.

Kit Includes

• 1x Aluminum Crush Washer - AN Sizing (size per your selection)

Applications

• ODs: 15.9mm OD, 17mm OD, 20mm OD, 25.3mm OD, 28.28mm OD, 33.5mm OD, 40mm OD, 47.5mm OD; IDs: 9.8mm ID, 11.3mm ID, 14.5mm ID, 19.3mm ID, 22.5mm ID, 27.2mm ID, 33.5mm ID, 41.5mm ID
• Common uses: banjo bolt joints, oil drain plugs, washer-sealed metric and AN-adjacent hardware
• Pairs with FLF Banjo Bolts and Magnetic Oil Drain Plugs