Availability of Aluminum Oil Bath Caps for AL-KO Axle on 2013 PJ Trailer

Updated 12/17/2025 | Published 11/03/2024

Question:

I have a 2013 PJ trailer with ALKO 10K axles. The bearings are oil bath with the original plastic caps. I would like to replace the plastic caps with the aluminum caps. Can you assist me with identifying the correct ones? The axle P/N is 402995 and the serial number is 042-67159-003-0679970-00010. The date of the axle is 03-12-12. I tried to purchase the Valcrum cap model ST-375, but the threads got stuck after 1/4 turn and would not go any further. Let me know if you need any additional information. Thanks,

asked by: Marc L

Expert Reply:

Hi Marc; the only aluminum oil bath caps we offer for an AL-KO with that capacity are the # VA35JR which you said don't work. AL-KO hasn't been around for a while so unfortunately the axle info doesn't help much. Regardless, we only know that the oil cap can replace an AL-KO 1531029 cap. There are a lot of AL-KO parts that were not industry standard, so I'm going to say sticking with the plastic caps is your only option unless you are able to find a standard hub that fits your current spindle and can use one of the other aluminum oil caps.

expert reply by: Robin H

Robin H.

12/15/2025

Hey Marc, were you able to stick with the plastic oil bath caps for your AL-KO axles or find a hub that let you use the aluminum ones? Knowing what ended up working could help others with older AL-KO setups.

Marc L.

12/17/2025

@RobinH. I ended up switching the hubs from AL-KO to Kodiak. Reason being, AL-KO axles are not made anymore and parts were difficult to find and a couple of the hubs had different thread pitches. It was easier to make the switch now and I was able to use the aluminum oil caps.