Availability of Oil Cap for 494 AO DexStar Hubs
Updated 09/12/2025 | Published 08/27/2025
Question:
Hi. I'm contacting you because I have a vintage 1973 travel trailer and I am looking for parts for it. It has the original 494 AO DexStar wheel hubs and I'm really trying to preserve them, but the plastic hub caps that contain the oil baths have begun to crack over time and the oil is seeping out. I've been looking for similarities online, but to no avail. The part number I have on record is Dexter 21-17. Is there an interchangeable replacement for this? O.D. of plastic flange is about 3½ inches, but I'm only going off of a tape measure.
asked by: Baily J
Expert Reply:
Hi Baily; the only thing we have that is close is the Replacement Oil Cap Kit for 9,000-lb and 10,000-lb Dexter Axle # RG04-300. However, this is designed for Dexter axles made after July 2009. The threaded diameter is 3.47" so measuring with a caliper would be best. Old parts like that can be hard to find, and often end up discontinued. It might be a good idea to take it to a local shop and let them try out some oil caps to see if you can get one that fits the old hubs.
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Product Page this Question was Asked From
Replacement Oil Cap Kit for 9,000-lb and 10,000-lb Dexter Axle
- Trailer Bearings Races Seals Caps
- Caps
- Oil Cap
- 3.50 Inch O.D.
- 3.50 Inch
- 9000 lbs Axle
- 10000 lbs Axle
- Redline
more information >
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Robin H.
9/12/2025
Hi Baily, did you have a chance to take your trailer to a local shop to try out some oil caps for your vintage hubs? I'm eager to hear what solution you found, as it could help others facing similar challenges with older trailers.