Rear axle oil

[paul wilks]

I guess this might well be of interest to Jupiter owners as well but that's only a guess! (Some pre war cars as well??)

I contacted Castrol (or what's left of it!) re oil for the rear axle of my Javelin. This is their response.
I assume that the axle does contain "yellow metal components" but would be grateful for clarification from those who know!
So my question is:
1.Do I go for EPX 80W-90 (no "yellow metal");
2.EP 80W- 90; OR
3.Universal 75W- 90?

This is Castrol's response.


"There were a number of different Hypoy oils – with different levels of EP additive. Normally “Hypoy” refers to hypoid gears and as such you would expect GL-5 rated oils. This would be the Castrol Axle EPX 80W-90

However, for some gearboxes that had yellow metal components which can be affected by the aggressive EP additives, a lower rating was required – GL-4, which would manual EP 80W-90. So if you are aware of yellow metals in there, go for the GL-4.



One other route would be the multipurpose Universal 75W-90, this is a high performance part synthetic and covers GL-4 and 5 ratings and is suitable for all applications, and should be easily available from the likes of retail outlets."

Thanks

Paul

[robert lintott]

For Paul , Happy new year . Is this connected with the nasty noise you experienced on the way home ?

re the rear axle , Castrol's advice seems sound . The additives which attack bronze etc components were developed after Jowett's days so the Jowett recommend was just a Hypoid oil . It is best to assume yellow metals are present so the less aggressive GL4 type suggested would be safest . Even so in wear terms it will probably be a better oil than the Hypoy 90 EP available in 1952. EP was "extreme pressure" in the hypoid gear system . Probably best to empty and refill with fresh but keep a watch for oil leaks into the rear hubs in case the new oil attacks the inner oil seals . I have in front of me a JCS inner oil seal which is made of modern materials , unfortunately my local garage could not get the old one out, we may have to try again ! best wishes Bob

[paul wilks]

Hi Robert. Happy New Year.

I have a distinct rumble from the rear nearside drum. Could be a bearing of course but I do tend to be a pessimist in these "Jowett things" as my better half will tell you. I cannot tell at this stage whether there is anything else but the rear axle casing does look to be rather wetter than usual. You can imagine I am thinking all sorts of things at present and until we have a bit kinder weather I won't be crawling about underneath to investigate!
All I can tell you is on the way home from the NEC (about 20 miles from home) there was a "crack" rather like running over a twig. My wife thought that is what I had done but the following rumble betrayed something worse than a twig! I am hoping it is not a broken half shaft! Or an oil seal!

Thanks for your thoughts on the oil anyway.

Paul

[Drummond Black]

Paul,
It will NOT be a broken half shaft. They are built to last. Check if the Brake Drum is tight and located correctly. Check correct End Float. ( 8 thou max rings a bell )
Have you looked at the layrubs, centre bearing support, Panhard Rod mountings , If all OK then pull the Brake Drum (s) and check the brake shoes, springs, Brake Drum, etc, An hours work. !!

Drummond

[paul wilks]

Thanks Drummond. As always the optimist.

I can confirm I have checked layrubs; centre bearing support; mounting centre and both ends, Panhard rod (both ends).
I'll get on and remove the hub! If end float is incorrect I assume there is info re rectifying it or is it a new bearing?

Paul

[Drummond Black]

Paul, if you say you heard a " Crack" then I doubt you are looking at outer bearing failure. They tend not to wear to any great extent. I would concentrate on looking for a failed part. Now are you sure the rumble is coming from the rear end ? If anything I would look at the brake drum fit and tightness. End float can be adjusted but requires a bit of care.

Drummond

[Jack]

Some good info on axle endfloat here that might help: http://www.jowett.net/forum/viewtopic.p ... oat#p15986

I'd certainly get the drum off and have a look - could be something very simple has come loose or failed, and also will give you a chance to check for leaks or other potential problems.

Jack.

[robert lintott]

Paul, If it was a noise loud enough to hear in the car then it could be more than a twig ! Have you checked the road wheels , which are known to develop cracks and if so could run out of line ? Did you look at the trailing arms , which are known to break ? All the other advice looks good so a busy time . Best wishes Bob

[paul wilks]

Hello Bob etc. I checked the trailing arms. That was my first area of concern but both are okay. BUT Bob, you have got me thinking about a possible wheel failure. I think I'll try that first.

Paul