oil leaking from new trany with redline syth oil

[recordsj]

1500 mg midget with J-type laycock OD.
I have rebuilt 1500 tranny and J-type laycock OD.
The the british car shop that did the work they put in required conventional gear oil in the tranny. I drained it after several hundred miles and placed redline MT-90 syth gear oil in it and now it is leaking. I have heard that this syth oil can do this, anything that can be done as opposed to going back to conventional oil?

 

[jlaird]

So drain what you got and go by the manual.

 

[recordsj]

I want to use redline mt-90 synthetic since it has the chemistry in it that won't corrode brass/bronze parts in the transmission. Other GL-4 and GL-5 conventional gear oils can corrode brass/bronze parts in the transmission.

see tech notes from link below
https://www.redlineoil.com/whitePaper/13.pdf

 

[aeronca65t]

~Rimmer Brothers~ use normal EP90 gear oil in their J-type overdrive units.

In fact, they *require* that you use it in their rebuilt units or they will not honor the warrantee.

I would say they know more about the J-type overdrive unit than almost anyone else anywhere.

Just food for thought....it's your car so do as you wish.

 

[recordsj]

I would use conventional oil, but because of the bronze parts in the transmission which the chemistry of GL-4 nad GL-5 conventional oil will corrode and eat away at these components. That is why I use redline sythetic MT-90 gear oil.

 

[GrahamP]

This could be an endless loop!
Now return to 1st and 2nd replies.

I would guess that the original designers knew what oil they would use and what effect it would have on the materials in the gearbox.

Now go back to your original question and response, do you actually want an answer other than use the synth oil and let it leak?

 

[recordsj]

I was trying to bring the discussion off of the overdrive.
I would prefer a leak because of using sythetic oil as opposed to using convetional oil and having bronze parts in the transmission corroding.
I am bringing up this question to see if there are any other options.

 

[Westfield_XI]

Did the original designers know that they would change the formulation of the oil? Should we all start using new blend oil w/o the zinc that protects our valves. There are a bunch of different oils listed on ?my filler cap: should I try to find Duckham's here in the USA because it was recommended back in 1967. Why should we try to pretend that there has been no changes in the last 30+ years.

 

[recordsj]

I did come across this site www.macysgarage.com/myweb6/gear_lube.htm
Does anyone else have any other reference on the net concerning this issue (conventional gear oil corroding bronze parts in transmission)?

 

[GrahamP]

I don't propose that one pretends that oils haven't changed or improved in the last few decades, if new oils can be used successfully then by all means use them. On the other hand, if there is a problem because newer formulations creep too much or are too thin, etc then why try to use them when the "correct" oil is available and does a perfectly decent job.
Assuming the gearbox has been reconditioned with standard parts and not some exotic materials not available 30 years ago then there isn't really a valid reason for changing the type of lubricant. From what I remember from repairing gearboxes in my youth, most faults were bearings, shafts and synchro cones, not bronze bushes which just seemed to soldier on quite happily for years.
The synthetic oil is probably excellent when used in the gearbox it was intended for and may well be just as good in the midget box, but if it causes a leak then where is the benifit?
The only way to be sure if it is the oil or the gearbox seals is to drain, flush and refill with standard EP 90. If it doesn't leak, there is the answer. If it does leak then either the seals were faulty initially and coincidentally started leaking after the oil change, or the sythentic oil has damaged the seals, either way the seals will need changing again. This could be an expensive excercise if you finally decide that the synthetic oil is causing the problem and damaging the seals as you will have a minimum of two seal changes to pay for!
Good luck, Graham.

 

[Westfield_XI]

Re: oil leaking from new trany with redline syth o

I thought the problem was that a "correct" oil was not available due to formulation changes, thus the experiment with synthetic. Was that an incorrect read of the problem?

Isn't this somewhat like the situation with engine oil being changed to help meet emission requirements by the removal of zinc. Or going waaaay back, like the removal of lead from our gasoline back in the 70's. Sure the manual calls for high test gas, but they never imagined back when they wrote the "book" that the fuel would become unleaded.

Does anyone know if this is an issue with the Datsun 210 transmission?

 

[recordsj]

Re: oil leaking from new trany with redline syth o

Did some research on the net and came across this link
www.oilanalysis.com/article_detail.asp?articleid=496&relatedbookgroup=OilAnalysis?b1b7cb08

which from that site (I also found a couple of others that said the same thing). As long as you use a name brand gear oil, the issue of conventional gear oil corroding away bronze parts in the gear is not a problem anymore in modern gear oil. So from that there is not necessarily a need to go to synthetic gear oil like redline to avoid this issue.

 

[GrahamP]

Re: oil leaking from new trany with redline syth o

Recordsj doesn't mention anywhere that EP90 has changed (it may well have! But I don't know one way or the other) just that he would prefer to use the synthethetic as it has better properties regarding phosphor bronze.
If EP90 has changed then Recordsj has a point, but if not, then "if it ain't broke then don't fix it!" would seem to be very appropriate
Graham.

 

[recordsj]

Re: oil leaking from new trany with redline syth o

I do not know if EP90 chemistry has changed, other than I seen it said that modern conventional gear oil will eat away on bronze component. From the website I posted from my previous post (reposting website)
www.oilanalysis.com/article_detail.asp?articleid=496&relatedbookgroup=OilAnalysis?b1b7cb08
that this appears to be a myth and there is no problem in using name brand conventional gear oil.

 

[zimmy]

Re: oil leaking from new trany with redline syth o

if it hasnt rotted by now, its probably not gonna...
id use the regular oil...synthetic is just too advanced
for some of these old cars and crawls through cracks that
normal oil cant ....zimmmy

 

[jlaird]

Re: oil leaking from new trany with redline syth o

I am going to answer one more time then ignore this thread, use the types oil recommended in the drivers manual for the car in question.

You will not find synthic oil in that list, never never use it. It leaks in our trannys, they were not designed for it.