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BWP · Brakes & Wheel End
M684
In stock · ships from Knoxville
This is an outer axle spindle nut used to secure the wheel hub assembly onto the spindle of a trailer axle.
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Verified fitment for 2 applications
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All confirmed applications for this part number.
Other applications
Other applications
Fitment data is based on manufacturer catalog listings for the BWP M-684. The original search results also returned a clearly erroneous cross-reference for a Ford Escort; this is not a valid application for this axle nut.
Part data verified against 5 catalog sources
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It threads onto the spindle after the hub and bearings are installed, working together with the inner nut and a locking washer to maintain proper bearing preload and keep the wheel securely attached. You typically replace this nut if the original is damaged, stripped, or rusted, or during routine wheel-end service. It features a 2-5/8"-16 thread and a 3-1/4" hex, fitting many standard trailer axles.
Part Number: M684
AXLE NUT OUTER
Unit: ea
Dealer: Knox Trailers
Compatibility, alternatives, and more
Parts commonly needed alongside brakes & wheel end
