Gearbox oil

[Clifford Pope]

I am about to swap my present ailing manual box with A-type overdrive
for an identical  spare I have been rebuilding. Previously,
knowing the box was on its way out, I have been a bit careless about
what oil to top it up with, just using some unknown SAE 90 oil I
happened to have around.<br>
But now I want to fill from scratch with the proper oil.<br>
What should that be? I can\'t find a mention under Specification on the
website, and my handbook is silent too. I have another book,
contemporary with the car (1964) which says SAE 90 EP. I thought EP was
for differentials - is that correct? I know there is some issue with
the bronze bearings not liking something, but what?<br>

[David Withers]

Hello Cliff.
You are&nbsp;quite right&nbsp;in saying that EP 90 is normally an oil for differentials but it also happens to be the correct oil for the Triumph manual gearbox.&nbsp; Nothing else is suitable.
As you may know, some&nbsp;other car makers specify engine oil or even auto transmission oil, depending on the&nbsp;design of the synchromesh and, to an extent, the gears and bearings.&nbsp; Any variation from the specified oil is asking for trouble.
Some say that&nbsp;bronze bearings do not&nbsp;tolerate synthetic oil.&nbsp; I&nbsp;learnt this <U>after</U> I had filled up with synthetic but have not had any trouble in the seven years since I put it in.&nbsp; When&nbsp;filling again I\'ll be using mineral oil just to be sure.
Regards, David.

[Clifford Pope]

Thanks David.
EP 90 doesn\'t seem to be readily available. Will EP 80/90 do?

[David Withers]

Cliff,
I\'m a bit out of touch on gear oils so I&nbsp;checked several oil-related websites for info.&nbsp; EP80W/90&nbsp;now seems to be&nbsp;the standard&nbsp;recommendation&nbsp;for cars&nbsp;where EP90 is specified.&nbsp; EP80W/90&nbsp;should make for slightly easier&nbsp;gearchanges in cold conditions whilst giving the same&nbsp;protection as&nbsp;EP90 when hot.
The synthetic grade I used was&nbsp;75W/90.&nbsp;&nbsp;The gearchanges are quite fast and smooth&nbsp;compared with some other Triumphs I\'ve driven but I haven\'t done any back-to-back tests so&nbsp;I couldn\'t be sure this is solely due to the oil.&nbsp;&nbsp;I intend to change to mineral oil&nbsp;in the spring and will now be using 80W90.
David.

[David Withers]

Cliff,
I\'ve&nbsp;searched on this question a bit more, using the internet, and there seems to be a great deal of contradiction about these oils.
It seems that EP 80W/90 can be to GL-4 spec (as the old EP 90) or to GL-5 spec.&nbsp; Some out there say that old cars should use only GL-4.&nbsp; Perhaps best to play safe and look for GL-4 on the bottle?
&nbsp;

[Clifford Pope]

Thanks again David.
I\'ve tracked down some EP90 (it\'s only Halfords that don\'t sell it) so have filled up with that. The gearbox and overdrive are fine now - see other thread.
&nbsp;
Cliff

[David Withers]

Cliff,
Thanks for coming back on this.&nbsp; I wasn\'t 100% comfortable with what I\'d found on the internet about these oils - too much contradiction.&nbsp; I don\'t think you&nbsp;can beat using the car maker\'s original specification!
I\'ll do likewise and fill my gearbox with EP90 -&nbsp;when&nbsp;the weather&nbsp;gets a bit warmer!&nbsp; You must be tough over there in the west, or else the Gulf Stream is keeping you warm.&nbsp; It\'s very drafty and cold here in the Cambridgeshire fens.
David.

[Clifford Pope]

Yes, when you\'ve had too much Christmas cheer there is nothing quite like going out to a cold draughty garage and lying under the car for a few hours with your hair in a puddle of old oil.
The annoying thing now is that the clutch release bearing has suddenly developed a slight squeak when the clutch is in the half-engaged position. This was all new very recently, and I checked it carefully while the gearbox was off. The noise is intermittant, but seems most prone after standing warm for about half an hour.
A quick squirt of WD40 through the vent hole stopped it immediately, but it has now returned. I have tried a shot of lubricant spray, so I\'ll see what that does.
It was silent before, and all that is different now is that the same operating shaft and bearing is now installed in a different bell-housing. I am wondering whether slight end-float on the operating cross-shaft could be responsible. The spring seemed OK, but I am wondering whether to try tensioning the lever to one side or the other.
On the Volvo I stopped a very badly squealing release bearing by giving a squirt of ordinary oil from a can, but I am hesitant about introducing too much oil near the clutch.
Any suggestions (other than removing the gearbox again and trying another new release bearing!) would be most welcome.

[David Withers]

I don\'t know what others think but I\'d be inclined to leave-be for a while and see if it gets worse or better.&nbsp; Hopefully your squirt of lubricant will be enough.&nbsp; It surely can\'t be anything&nbsp;major if an ultra-thin fluid like WD40 had an effect.
Good idea lubricating through the vent hole.&nbsp; That reminds me of when a chap asked for my uncle\'s help&nbsp;in about 1960 because&nbsp;his Humber had come to a stop with a slipping clutch on the way&nbsp;to his daughter\'s wedding about 40 miles distant.
My uncle&nbsp;suspected the problem to be at least partly due to oil contamination so he drilled a hole in the clutch housing and&nbsp;squirted the contents (CTC?) of an old-fashioned fire extinguisher through it.&nbsp; This rejuvenated the clutch and the car drove away.&nbsp; I wonder if&nbsp;they&nbsp;reached the church in time!