Areolite nut or Philidas nut for wheel bearing retaining nut

I am looking at using one of these types of locking nut for the front and rear hubs to replace the castle head nuts with the split pins, the only draw back I could think of is; maybe I will not be able to feel how much I have tightened the nut up before I back it off a little on the front hub bearings ?
I have used this type of nut on other parts on the car but maybe this might not be suitable for the front hub bearings
anybody else used these for the front wheel bearings? or have any recommendations ?

Whats wrong with the castlated and split pin…it works … Steve

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Jaguar used the slotted nut and split cotter pin up through at least 1974 that I know of.
You are correct that you don’t just tighten these up and stop; you back off so the hub rotates freely, then put in the pin.
I would be afraid that any other kind of nut would loosen up on the left and tighten up on the right.

Just looking at an alternative as getting the cotter pin in and out can be a pain


Then I suggest better tools are a better investment.

Definitely stay with the original. Long nosed pliers can easily reach into the hub.

As all of the above comments, also the split pins are not removed that often.

Thanks I did not realise there is a hold in the hub to reach the split pin on the castle head nut !

Another thing, use the right size split cotter pins, and just bend one end about 30 to 45 degrees. L105/12U is 5/32" diameter and 1-1/2" long.

Some DPO used pins way too long and twisted both ends of them around like pretzels. It took me an hour to get each of them out.

Rob’s right, that’s the secret to its simplicity.

Mike (and Steve) - I know I am being pedantic, but a “Castellated Nut” although superficially some similarity, is dimensionally (most important) and technically different to the SLOTTED NUTS as used by Jaguar in most applications, including the Hubs.

For the benefit of Australian and I dare say many other non-USA listers following this thread - be very very careful when you buy Split Pins…
Since Australia converted to metric in the 1970s, over a period of some years all material stock that used to be in imperial sizes, gradually changed to metric sizes, especially for things made in China, as are most split-pins sold in Australia. So when you go to a fasteners shop, and buy Split pins, you will find that despite the packaging labelling stock in both metric sizes and imperial sizes that the contents will be metric sized, the packets showing Imperial sizes will be a soft conversion. So in the case of 5/32" marked packages (5/32" = .156" = 3.96mm) you will find the split pins will be actually 3.5mm or 4.0mm rather than 5/32". For static applications and some sizes, in the real world it wont matter, but in certain mobile applications where the correct sizing of the split pin within its imperial sized original hole does matter, it can be problematic - being too tight thus installation issues, or to loose and thus vibration/breakage issues… Once I found out the hard way many years ago, and investigated this problem/issue rather than assess every split pin application on its technical merits, I instead chose to make a bulk purchases of all the various sized split pins likely to be needed on my XK restoration - plus lots of extras - from the good old USA, where split pins (or should I now say Cotter Pins) are still made in Imperial sizes - with the size of their home market big enough that the foreign factories (Mexico???) making them, supplying in correct imperial sizes… Diameter is of course the issue, marginal difference in length is irrelevant.
There are a number of on-line USA split pin suppliers, for any Brits, Europeans, Australians etc to easily buy in imperial sized split pins, and then all you have to worry about is that there is a wrong way and a right way to install/secure correctly sized split pins, so even in extreme environments (such as big-end bolts) you will never have a breakage problem…

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Yes, they are slotted nuts. Castle nuts have the slotted section turned down to make the hexagon circular and slightly undersized. The only reason I can think of an application for these is to have a flush split pin by wrapping the tails around the circle. It makes the nut smoother and safer. They are fitted to the tie rod ball joints on my MG TA.

At the risk of criticism, don’t keep pumping grease into that nipple - don’t use it at all, and just use it to plug the hole. Just pack the bearings individually with a good bearing grease and leave it alone. The greases in the ‘good-ol-days’ liquefied with heat and gradually ran out of bearings. The reformulated greases solved that problem 60 or 70 years ago.

This is a slotted nut. :rofl:


This is a castle nut, named Peeves.


That slotted nut is a slotted tube nut. Smith’s used them by the millions in 2BA brass for the terminals on the back of various instruments. They are also used in the rear number plate light box on the Mk IV to hold the glass retainer strips, but smaller at 3BA.

I learned a lot about nuts especially with the up coming UK general election !

1970 they still recommended to fill the hub until it comes out the vent. Huge mess. The grease I use (NLGI 2) liquifies and runs out of the vent hole…

Split pins should never be installed so the legs wrap around the nut. It’s far weaker. Bad practice.

It has to be like in Rob‘s picture. His installation is very nice especially in that location, although generally Jaguar folded the leg over completely and as far as I know cut the other leg off flush, or at least they did so in the 60s.

That may be the practice with disc wheel hubs, to ensure there is no clearance problem with the hub cap. Wire wheel hubs have more elbow room.

I bought some 5/32" x 1-1/2" split cotter pins today; they are 84 cents for a pack of 4 at Menards.
Ever since I learned that the term cotter pin means something different in Australia, a wedge pin for bicycle pedals, I’ve taught myself to say split cotter on this forum, so as to cover the terminology in all English speaking countries. :slightly_smiling_face:

Brown split cotter pins

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Good idea…
Even the British were somewhat ambiguous originally. The applicable British Standard was BS1574

BS1574 was first issued in 1949 and was titled SPLIT COTTER PINS
BS1574 as updated in 1958 was still titled SPLIT COTTER PINS
But the next update of BS1574 in 1994 changes the title to: SPECIFICATIONS FOR SPLIT PINS (INCH SERIES) reflecting what was the well established everyday and industry common usage terminology…

Jaguar themselves always used the term SPLIT PINS, as evident in their Spare Parts Catalogues…, and certainly in colonial Australia, always a ‘Split Pin’ , but as we know in USA its ‘Cotter Pin’

Was there an American called Mr Cotter ???

The pain (and joy) of Jaguar ownership!!! Unless you have a book of engineering data to support the swap - stay with the slotted nuts and cotter pins.