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Overdrive and tranny oil

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Legal Bill

Jedi Knight
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Hi guys. I did search, but I can't find the thread from a few month ago about the best weight and make of oil for the tranny and overdrive. I recall that one of you posted a link to a research paper that discussed the pressures measured on the bench using different oils. If you can point me to that thread I would appreciate it.
 
I didn't see the previous thread on this, but I have been told by several reliable sources (restoration shops, etc) that 30W nondetergent oil is best for a Healey transmission and O/D. The nondetergent part is important because almost all modern motor oils contain detergent. You have to look hard to find nondetergent.

I would be interested to hear other opinions on this, although I suspect it's discussed numerous times.

Keith
 
I've tried the redline. I found no difference in shifting, but did find that it leaks a lot more. Being it costs a lot more and it was leaking more, I went back to Castrol GTX 20-50. I change the engine oil, tranny and overdrive oil. I have a magnetic engine oil plug and the tranny has it's own large donut shaped magnet. I don't find much metal on those magnets when doing an oil change, so things seem to be working as intended.
 
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I bought a case(12qts) of MT-90 for 48 bucks on line, no tax and cheap shipping. It does leak out but I probably got a 10 year supply. The detergent suspends the microscopic particles while the non-detergent allows them to drop, safely to the bottom to the gear box. I do find smooth shifting and a quieter gearbox. But this is why they sell different flavor ice cream.
 
Hi All,

A while back I came across and posted a reference to this article (www.mgtoronto.com/pdf/Tech/Overdrive_oil.pdf ) that describes how a number of different oils function in our overdrives. It has always amazed me that different manufacturers using the same overdrive (Healey/Jaguar/Triumph/MG/Volvo) seems to have decided upon a different oil. Add to this list the relatively new synthetics and the fact that the old oils have had major formula changes and a good selection is often left to past experiences and the opinion. The experiments described in this article show how some of these oils function when operating in the overdrive and provide some direction.

I personally use MTL-90 synthetic and often find its foot prints on the floor.

All the best,
Ray (64BJ8P1)
 
Here's a question for the guys using redline, which I was once a user. If negatives are it costs a lot more, it leaks a lot more (and out of places it did not use to), then what are the positives? I did not find the shifting to be any smoother/easyer/quieter (which I thought it would be, wanted it to be, but was not. I was even willing to tolerate a bigger oil spot for better tranny performance/protection), than regular non detergent oil, Castrol GTX 20-50. When I changed both oils, Redline/Castrol, neither one showed any more metal particles than the other, so it seems they were both lubricating the gears the same. The shifting was smooth with both, overdrive engaged and disengaged the same with both. What am I missing? Both shifted the same, both protected the gears the same, but Redline costs a small fortune and it leaks a lot more, increasing the small fortune that Redline will make from me. (Maybe this product works better in modern cars that are suppose to use synthetic?)

I take really good care of my car appearance wise and running condition. I stay on top of all mechanical issues and change all the oils regligously. If there is a better product for my car, I want to use it. But found no improvement with Redline. It may sound good on paper, but when I used it, I found no difference. What would be different with my tranny/overdrive than other Healeys' where others say they do. Sometimes I think the way products are written up provide a placebo effect when we use them.
 
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It's interesting to hear the different opinions on this and read the different "authoritative" articles. Of the two articles, the one posted by Ray (www.mgtoronto.com/pdf/Tech/Overdrive_oil.pdf) is the only one with hard data concerning the performance of different oils in an overdrive unit. They seem to clearly state that 30W nondetergent oil is the best, so I guess I echo AUSMHLY and ask why Redline 90W is so popular?

I'm not trying to provoke anyone with this. I'm honestly just curious about it. My tranny and O/D are in pretty good shape and I want to take care of them the best I can.

Keith
 
Hi Roger/Keith,

For my part, I don’t disagree with any of your comments andpicked Red Line as an alternative to the 30W non-detergent I began to finddifficult to acquire. As the article inmy last poste indicated, the Red Line seems to find its way out oftrans/overdrive areas I had never had a problem with, however, the synthetic natureof the fluid is also acknowledged to provide good non-foaming protection forall the metals in the unit at the correct viscosity over the rang of operating temperatures. I willprobably continue to use the Red Line MTL until I find a better fluid …. at least for the time being.

Ray (64BJ8P1)
 
RAC68 said:
Hi All,

A while back I came across and posted a reference to this article (www.mgtoronto.com/pdf/Tech/Overdrive_oil.pdf ) that describes how a number of different oils function in our overdrives. It has always amazed me that different manufacturers using the same overdrive (Healey/Jaguar/Triumph/MG/Volvo) seems to have decided upon a different oil. Add to this list the relatively new synthetics and the fact that the old oils have had major formula changes and a good selection is often left to past experiences and the opinion. The experiments described in this article show how some of these oils function when operating in the overdrive and provide some direction.

I personally use MTL-90 synthetic and often find its foot prints on the floor.

All the best,
Ray (64BJ8P1)
Click to expand...

Thanks Ray. That was the article I was looking for. I'm having the problem described. The overdrive is not disengaging properly after the overdrive has run for a while. Now I have to find non detergent 30 weight.
 
Legal Bill said:
Thanks Ray. That was the article I was looking for. I'm having the problem described. The overdrive is not disengaging properly after the overdrive has run for a while. Now I have to find non detergent 30 weight.
Click to expand...

Bill, maybe the overdrive is out of adjustment? That could certainly affect when it engages and disengages. May not be an oil issue. Or maybe it's time to change the oil in the overdrive. When or how many miles ago did you do an oil change?
 
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Legal Bill,
I would be interested to hear where you find 30W nondetergent oil. I got mine from autozone, and the only brand of 30W ND oil was their own brand. Not to slam Autozone, but I don't know much about the quality of the oil. It would be nice to know of some alternatives.

Keith
 
I have used redline for about five years. There might be a slight improvement in shifting. The good news is my tranny does not leak, so that has not been an issue.
 
AUSMHLY said:
Bill, maybe the overdrive is out of adjustment? That could certainly affect when it engages and disengages. May not be an oil issue. Or maybe it's time to change the oil in the overdrive. When or how many miles ago did you do an oil change?
Click to expand...

It might be the solenoid adjustment, but it was working fine until the engine was good and hot. My brother was driving and he was playing with the overdrive in both third and fourth. A couple of times he forgot to shut it off before he shifted it down to second. So he gave it a good "work-out" and before I could tell him to leave it alone, I noticed it was not kicking out properly. Later in the drive, after it was out, I could not get it to engage. So she is now jacked up in the air and I'm going to take the GM synchromesh friction modified out (has about 300 miles on it) and try the pure 30w. I'm going to miss the GM Synchromesh. The tranny shifted slick as greased .... I use it in my Honda S2000. The stuff is great, but I'm concerned that it is foaming in the overdrive. It passed the basic electric test (ignition on, O/D switch on, push shifter to the right and I heard the loud click) so I think the electric side is ok. If the new oil does not clear it up, then I'll check the solenoid adjustment.
 
Legal Bill said:
On line I found Valvoline 30w non detergent. It ain't cheap at almost $7 a quart.
Click to expand...

Autozone $4, but given how rarely I anticipate changing the tranny oil, price is not really much of a consideration.
 
Hi Bill,

A friend had something similar happen and, upon investigation, found the rubberbutton normally located under the solenoid plunger had broken and was bouncingaround in the housing. All was well when he replaced this few-cent part. I havealso fused my solenoid circuit to protect the unit from burning out during asimilar situation.

HappyThanksgiving,
Ray (64BJ8P1)
 
I just use 20-50 castrol, the same oil i use in my motor. As the offical Bentley manual says to use! I never had any problems with shifting and the overdrive works perfectly! On cold days i just make sure the oil temperture is warmed up after about 5 miles or so before i engage the overdrive... As to avoid blowing out any seals! I used to run sae 40 wt in my Tr6... but the 20-50 seems to make the overdrive engage much smoother in my Bj8...
 
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