Gearbox oil

[ernie turner]

What is the correct gearbox oil for my 1972 tr6 please thanks for looking 

 

[RobH]

This question has been asked so many times - the latest about a month ago - and the are many old threads discussing and answering it.  You will find them if you do a forum search on Google by including the term  "TR Register forum " in the search string. 

(for some reason the forum search tool doesn't seem to recognise short words like 'oil' .)

 

 

Edited August 7, 2023 by RobH

[dblenk]

i put Halfords mineral gbox EP 80-90 oil grade GL4 in mine

think a grade GL5 has synthetics doesn't like the brass bits or so i was told

 

please check though

 

David

 

Edited August 8, 2023 by dblenk

[Tim D.]

1 hour ago, dblenk said:

i put Halfords mineral gbox EP 80-90 oil grade GL4 in mine

think a grade GL5 has synthetics doesn't like the brass bits or so i was told

 

please check though

 

David

 

Agree with David. But was given a hard time on the stag owners club where they use GL5 as apparently modern GL5 is OK with yellow metals.. Not checked this our as GL4 seems to work fine

Tim

[RobH]

GL5 normally has high levels of the suphurous additives necessary for Extreme Pressure performance and it is these that attack brass and bronze. Although the oil or may not be 'buffered' with other additives and be said to be safe, it is intended for use in differentials where EP is good.   It still isn't suitable for use in synchromesh gear boxes. 

https://www.widman.biz/uploads/Transaxle_oil.pdf

[Mike C]

I had my gearbox oil replaced by mistake with GL5 after a clutch replacement.

The GL5 was far too slippery for my synchromesh to work properly and it caused jumping out of second gear at high throttle openings.

It took two changes of GL4 for these problems to disappear completely.

[KiwiTR6]

On 8/9/2023 at 1:44 AM, RobH said:

GL5 normally has high levels of the suphurous additives necessary for Extreme Pressure performance and it is these that attack brass and bronze. Although the oil or may not be 'buffered' with other additives and be said to be safe, it is intended for use in differentials where EP is good.   It still isn't suitable for use in synchromesh gear boxes. 

https://www.widman.biz/uploads/Transaxle_oil.pdf

Thanks for this Rob.  Based on the recommendations it includes I've just ordered 2L of Nulon 75-85 full synthetic GL4 for my car.

Gavin

[JohnC]

...and here's what Overdrive Repair Services say:

Quote

 

Original literature has said the Healey gearbox and overdrive should be using a mineral engine oil. However, the exact same overdrive on a big Healey will also be fitted to a Triumph – which also states to only use gear oil.

If you would like to use a mineral based oil, many experts agree that brass syncro gearboxes should be using engine oil. This is only before some mineral gear oils have additives which may corrode brass syncros.

When using engine oil, avoid using a ‘friction modified’ engine oil. As the syncro cone relies on friction to operation, if the oil is too slippery (‘friction modified’) the syncro is likely not to work. This is the main factor of why people choose to use a mineral engine oil which doesn’t contain friction modifiers.

 

So really you have quite a choice. I had problems when I had a recon OD (from ORS) fitted and filled with GL4. Swapped to engine oil (Penrite HPR30 20W-60) and haven't looked back for the past ~10k miles.

YMMV
JC

[ntc]

2 hours ago, JohnC said:

...and here's what Overdrive Repair Services say:

So really you have quite a choice. I had problems when I had a recon OD (from ORS) fitted and filled with GL4. Swapped to engine oil (Penrite HPR30 20W-60) and haven't looked back for the past ~10k miles.

YMMV
JC

Been telling you that for years as I was told by the gearbox guy that knew his onions, never had any issues and never any oil leaks.

[Rogcastle]

John

Can I ask what the problem was.

Roger

[Nigel Triumph]

I've always used EP80/90 GL4 Comma or Halfords (probably from the same blending plant). They've worked fine in my TR6 with A-type OD and GT6 with D-type OD for the past 20+ years.

I also use the same oil in the differentials.

Nigel

[astontr6]

On 8/8/2023 at 2:21 PM, Tim D. said:

Agree with David. But was given a hard time on the stag owners club where they use GL5 as apparently modern GL5 is OK with yellow metals.. Not checked this our as GL4 seems to work fine

Tim

The GL5 problem was killed off by the oil companies over 25 years ago as per Penrite Tech Dept.

Bruce.

[ntc]

I find this very funny, all those that say this oil is incorrect go very quiet  Where is Hamish and Cox ? To prove it wrong 

[RobH]

I think Mike's reply in the sixth post was the most telling 

 

[RogerH]

I think the only person(s) that can give a true/honest answer is somebody trained in the chemical composition of oils.

No matter where you look there are contrary responses.

I'm happy using gear oil in my gearbox.

And Diff oil in my diff

And thus Engine oil in  my engine.

 

Roger

[ntc]

22 minutes ago, RogerH said:

I think the only person(s) that can give a true/honest answer is somebody trained in the chemical composition of oils.

No matter where you look there are contrary responses.

I'm happy using gear oil in my gearbox.

And Diff oil in my diff

And thus Engine oil in  my engine.

 

Roger

That’s the point Roger people believe what they are told and forget about selling sand to Arabs , you tell me why mineral oil works in Mg gearboxes and not others? I have used good quality mineral oil for over 35 years and no problems indeed the last car I sold the buyer asked if it was a mx5 gearbox it was not, gear oil covers problems elsewhere ie noise and leaks been there done that.

[Hamish]

3 hours ago, ntc said:

I find this very funny, all those that say this oil is incorrect go very quiet  Where is Hamish and Cox ? To prove it wrong 

I’m here !!

what would you like me to say ?

i use gear 40 oil as per Pete Cox and son recommendation.

there said it. 
 

is there an element of using what is recommended by the builder so they can’t say “you used the wrong oil”

PO used ep 80-90 for decades successfully but it does stink and I had gearbox and od issues - god know why as I don’t stress my drive train ….. much 

all good now tho

[ntc]

2 minutes ago, Hamish said:

I’m here !!

what would you like me to say ?

i use gear 40 oil as per Pete Cox and son recommendation.

there said it. 
 

is there an element of using what is recommended by the builder so they can’t say “you used the wrong oil”

PO used ep 80-90 for decades successfully but it does stink and I had gearbox and od issues - god know why as I don’t stress my drive train ….. much 

all good now tho

Sand and Arab as I said but proves nothing, take a look at the old videos posted by the club where Peter made a speech at a gathering. Enough said.

[Hamish]

I like sand

[RobH]

6 minutes ago, Hamish said:

I like sand

so do these chaps

 

[ntc]

Excellent advice 

[RogerH]

Excellent.

 

Roger

[KiwiTR6]

Has anyone tried 10W40 motorcycle oil?  Formulated for gearbox lubrication and wet clutches, I've never seen a gearbox fail from it's use.  It may in include components that preclude it being used with yellow metals, no doubt someone on the forum will have the answer!

[Hamish]

1 hour ago, RobH said:

so do these chaps

 

Well that’s the Shelton mallet forum meet up entertainment sorted then. Just need a couple of volunteers 

Edited August 11, 2023 by Hamish

[Tim D.]

I guess in the end the issue can be broken down into a few things.

1) oil that allows the gearbox to function correctly  (e.g. synchros function) (easy to test)

2) oil that allows maximum longevity of a gearbox (hard to test)

3) oils that positively damage gearbox internals (medium hard to test) 

Find the solution to these and we will know the perfect oil for a tr gearbox. 

I use gl4 gearbox oil.. I've had 2 gearboxes fail and 4 run fine....

The two failures where both lay shaft bearings. One was an original from start of life gearbox with >150k miles so fair enough. One was freshly rebuild badly with sleeved bearing surfaces on the lay shaft. 

Not sure either was oil related :-)

Tim