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National · Brakes & Wheel End
370031A
In stock · ships from Knoxville
This is a National Red 37 Series oil bath wheel seal. It's a unitized, spring-loaded nitrile seal designed to keep axle lubricant in and dirt, water, and debris out of the wheel hub.
Confirm the part fits before you buy. Applications and interchange numbers are researched and audited per part.
Verified fitment for 11 applications
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All confirmed applications for this part number.
Freightliner
International
Kenworth
Peterbilt
Other applications
Freightliner
International
Kenworth
Peterbilt
Other applications
Fits many heavy-duty drive axles, particularly Mack 44,000 lb drive axles. Verify your axle model and hub dimensions before ordering; the seal fits hubs with roughly 4.25 in shaft diameter, 6.26 in bore, and 1.19 in width.
Part data verified against 5 catalog sources
Numbers this part supersedes or interchanges with. Showing 14 of 14.
Different year, make, or config? Get a confirmation against your truck in under a minute.
It's commonly replaced when a wheel seal starts leaking or as part of a routine wheel‑end service on heavy‑duty drive axles.
Part Number: 370031A
WHEEL SEAL
Dealer: Knox Trailers
Compatibility, alternatives, and more
Parts commonly needed alongside brakes & wheel end
