rear diff oil leak

[dal2.0litrefrogeye]

Hi all, im a newbie to this forum , just mechanically restored my wifes 64 4.2 fhc ( vse build engine , new clutch , gearbox rebuild ) and dropped the rear end renewed all bearings , bushes etc , had the diff looked at and all was/is in top condition ( no need to stripp was the guys words ) when i fitted it back into axle cradle i fitted a new alloy diff cover c/w with breather tube , now to the point on light loads all is ok but once warmed and given a bit of stick ( motorways and fast up hills ) the diff breathes and pushes oil out of the breather ????? , i only filled the diff untill the oil trickled out of filler hole , so idont think its over filled , admitally the breather sits at 1 oclock rather then the straight up 12 oclock ( its where it went tight )but it is ony just off the vertical im thinking of fitting a length of tube to breather like i used to when i used to off road ???? , anyone else had this problem ? cheers, Darren

[christopher storey]

It should not be pushing oil out. The tube standing at 1 o'clock should make no difference . What oil are you using?

[dal2.0litrefrogeye]

Hi im using a 50:50 mix of ep 80/90 and gl5 ls oil , its what iv always used, put it this way its not a light synthetic oil ??

[christopher storey]

I am a bit hesitant about mixing. I recall Castrol stating that GL4 and GL5 spec oils should not be mixed . Why not try an EP 75W/90 suitable for LSD? There is also a special Shell oil specifically made for high temperature Dana 44 gearset applications such as most of the Jaguar final drives

[dal2.0litrefrogeye]

Both oils are to GL 5 spec , and iv been doing it for yonks without problems, but i dont think the grade of oil, is the oil out of breather problem , gonna drain off oil tomorrow (Iv got a syphoning tool that collects the oil into a gaduated container ) fingers crossed it will have to much in it because of the alloy rear cover ( the inside dish is larger then a standard cover ) if that does nt work its getting an extended hose on the breather with an oil restrictor in

[dal2.0litrefrogeye]

had a good look today and a think about it , think iv sussed why its pushing oil out , dug out the original diff cover looked at it and then it struck me the original cover on the inside of the oil breather it has oil diflection/baffle plate , the alloy cover hasnt ???? :? so iv put a long hose onto the breather union and then over the axle cage into a catch can , lets see what happens ?????

[dal2.0litrefrogeye]

Hi all , after a couple of high speed runs all is ok no leaks or excessive breathing , woopie :D