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Triumph TR3 - Brassy Fines in Gearbox & Overdrive

During the 75,000 miles since my restoration in 1990, I have always used Valvoline 20W50 engine oil in my gearbox with overdrive. This was the recommendation from Ken Gillanders at British Frame and Engine in Temple City, California. I have never had any mechanical problems caused by this oil.

I drain the oil every 3,000 miles. It comes out looking like it went in. Except, there is a brassy looking paste in the ol that I drain from the gearbox and also later in the bottom of the huge brass plug on to drain my overdrive.

1,600 miles ago, I changed to Castrol 80/90 Hypoy GL4 oil. Will I see less of these brassy fines next time I drain it ?

Do others get this ?

Any explanations ?

Is it getting into the ball and needle bearings to cause pre-mature failure ?

Don Elliott, 1958 TR3A
Don Elliott

Don-I think the small amount of brass in the oil is normal. It comes from the synchros&thrust washers in the trans and the thrust washers in the OD. It shouldn't damage the bearings. Steel particles and grey sludge is another story. I have always used used 80-90 wt GL4 and have noticed the brassy sheen in the oil.

Hi guys. I noticed the sheen upon first draining my gearbox, but haven't looked at it since getting back on the road. I also used 80/90 GL-4.
I do have a wierd thing going on though. After the car has been up to operating temp for awhile, it gets more difficult to change gears. Coming out of a gear is ok, but getting into the next one takes a second.
When it's cold, it's smooth as silk.
Any clues?
Mike G. - '56 TR3
Mike Gambordella

I found that TRusty has been coming out of 2nd gear when decelerating, just as I let up off the gas in a neutral loading condition in 2nd. That's happened 5 times now in the last 2,000 miles, the first while between turn 5A and 5B (Moss Corner) at Mosport. What a shock ! But it wasn't in a race. It was during the lunchtime tour or parade lap where you can go whatever speed you want to (or feel like doing), providing you never pass the car in front of you in the "Parade". At times we were stopped too !

I have always had this brassy sheen in the oil. As for the grey sludge I wipe off the magnetic plugs I use for the drain plugs for the gearbox as well as the overdrive, it is also very fine. I also put two very powerful magnets in the mesh screen basket that is in just above the large overdrive brass drain plug. I always clean out this basket and wipe all the magnetic sludge off these 4 magnets.

I also suspect that it's the 2nd gear synchro (they all have about 160,000 miles on them) as well as the front face of the brass or bronze "top-hat" bushing for 2nd gear.

Check out this thread on the TR6 site too. They usually have a lot of good answers where I have learned a lot by checking with them.

As for harder to change, Mike, you can take it out of gear just by releasing on the gas and tug it out into neutral. Then tap the gas and try it into next gear when shifting up.

How is it when you double de-clutch while downshifting ? At TRA, I think that out of over 75 TR's, there where fewer than 5 of us who knew how to double de-clutch !!! The trailer queens don't even know what that is !!!

Don Elliott, 1958 TR3A
Don Elliott

Don, It does shift up easier when tapping the acceleartor in between, but I would prefer not to.
As for double de-clutching on the downshift, I must admit I've never heard it called that, so I'm assuming you mean the typical double-clutch approach. (guess I fall in w/ the other 70 fellas who didn't know)

Actually, my car downshifts fine when I use the normal method of clucth in, tap the gas, throw the shift. If I'm in a corner, that's followed up by putting the tires on the line and standin' on the gas!

BTW, did my e-mail get through to you okay?

Mike G. '56 TR3
Mike Gambordella

I think that we are both writing about the same thing. Double Clutch is the American way of saying it and the Brits say "Double de-clutch". They "de-clutch" the engine from the gearbox twice, just like you do.

Sorry I can't help as to what to do about the slow up-shift. I usually say, if it ain't broke - don't fix it. When you get more answers (say about next winter - or the next one after that) you might want to have a winter project.

You could go to the TR6 site down a few lines, tell them you have a TR3, describe what the problem is, what works right, etc. and ask them for answers. Mention if your gearbox is all synchro or only in 2nd, 3rd and 4th. Also mention if you have an overdrive.

They usually reply.

Don Elliott, 1958 TR3A
Don Elliott

I have driven almost another 3,000 miles with the Castrol Hypoy 80/90 GL4 gear oil in my gearbox. Today I drained it out and found the same amount of brassy or bronze flakes and fines as with the Valvoline 20W50 engine oil that I have been using for 72,000 miles with an oil change every 3,000 miles.

Ken Gillanders told me that the Hypoy GL4 oil will soak into bands in my overdrive. So I have gone back to the Valvoline 20W50 (Racing) oil for my gearbox with overdrive.

Don Elliott, 1958 TR3A

Don Elliott

Don, Did you notice any performance differences between the two oils? I take it the GL4 soaking into the OD bands is not a good thing. Haven't had mine apart yet, so I'm not sure exactly what that means. (perhaps the manual will clue me in)
Why, specifically, does Ken recommend the 20/50?
You seem to place a good deal of merit in his opinion, and you're not exactly a novice!

I did finally get the car up in the air and check my gearbox fluid level, and it was down about 1/2 pint. Since refilling, the shifts are a little better.

Perhaps after driving, the fluid settled between the gearbox and the OD unit, not having passed completely between the two while standing still?

BTW, we'll be home the weekend of the 20th - hope you can make it.

Mike G. '56 TR3

Mike Gambordella

Hi Guys:
The non OD gearbox I am presently running has not generated any swarf,brass or otherwise and I am using 80/90 Hypoy GL4.The OD box which I am installing this winter was run on Hypoy and there was no evidence of swarf in the oil or in the dirt trap in the big brass nut under the filter basket.There was however black gorp in trap which did not appear to contain any metallics.God knows when the PO last changed the oil.
I am going to use Hypoy 80/90 spec GL4 as recommended in the TR3 drivers manual sixth edition as issued with the cars in the 1961 model year.This was a change from the SAE20/50 recommendation of previous years.I believe it was because hypoy has a much greater surface strength than engine oil.
I contacted OD Spares in the UK and they say that you can use anything from automatic transmission fluid to Hypoy 90 in the OD unit.However they say you should use what is recommended by the manufacturer of your vehicle.

HI again Guys:
Another thought on brassy fines.OD Spares also said not to use oils with anti-friction additives because they cause corrosion of the brass syncro rings.That is why Hypoy GL5 is not recommended.Maybe some other oils including various makes of modern 20/50 have anti-friction additives, hence the brass swarf.

This thread was discussed between 14/08/2003 and 05/09/2003

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