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Triumph TR6 - Synthetic Oil / Stabiler

Hi Guys,
Something else to ponder for us TR owners...
my brother-in-law and a close friend who are both mechanics recommended that I try Lucas Heavy Duty Oil Stabilizer in my 75 TR6. Their combined years of experience spoke highly of this product.
I have good oil pressure normally but I noticed that adding the stabilizer increases my pressure approx.
10 - 15 psi.
They also suggested using synthetic oil at the same time, they say that it will not cause any seals to leak and if anything will help swell seals. So in it all went on Monday and as I said the oil pressure did increase right away. I'll be watching everything engine wise closely over the next few weeks.
Lucas has a web site WWW.LUCASOIL.COM
I hope they notice this and send me a free case !!

We are going to open up a can of worms here but I confess I also use Lucas HDOS. My pressure also increased but I Know that this winter will be spent doing the lower end end done. I am about 25% Lucas 75% Castrol GTX 20W50. I also run 50% HUB OIL in the tranny. To boot I add The FUEL TREATMENT to the gas at fill up. I buy it directly from the distributor in Mississauga.
I will not put synthetic oil in the engine or anyplace else for that matter.
Good luck on the free case Charlie...the decals I got look good on the tool box.
Rick C
Rick Crawford

From 1990 to 1995, I used Castrol 10W30 in my engine and got about 600 miles to a quart. Over the last 6 summers, I have switched to 20W50 Castrol. I drive 6,000 to 10,000 miles a summer (64,000 in 11 summers and already 2,650 miles this summer) and I believe in the old addage, "If it ain't broke, don't fix it !".

To use synthetic oil and only drive say 2,000 miles a year is a waste of money ! When you have to change it once a year !

And never use synthetic in a TR gearbox. It's so slippery your syncros will be slipping out and last year a TR racer totalled his TR in a race while coming into a fast curve and suddenly found the synthetic had caused it to fall out of gear !!!!

It's just not worth it.

Don Elliott, Original Owner, 1958 TR3A

Don Elliott

Well, I've been using 10W30 Synthetic in the engine for approx. 10 years (1000 miles to the liter), 85/90 Synthetic in the Gearbox for approx 8 years. The engine once had the Slick 50 Synthetic additive added, and the gearbox once had the Slick 50 Manual Gearbox additive added. Never any problems.

Correction to above, the gear oil is 75/90.

Synthetic Oil in the gearbox will also create problems if you have an overdrive. The sliding cone has linings on it will react adversely with the synthetic. I also heard of several people having syncho problems and slipping out of gear.

Regular oil (ie mineral) today is of excellent quality and seems like there is more downside than upside using the exotic stuff on old technology engine with low tolerances. Even owners of vintage hardware like old Ferrari's Porsches ect don't use the synthetic stuff. Stick to the mineral type ie Castrol GTX, Quaker state, Kendal GT1 and make sure the weight is correct ie 20W50.

Besides I don't even use the synthetic in my new every day car (Acura CL) and that is worth about 3 TR 6's.

Bottom line it is a waste of money for a car that we drive 3000 miles a year and besides the real advantage to synthetic is excellent lubrication at a lighter weight and winter protection (easy starting at low temps). Or TR's need heavy oil for cooling and preventing burning and leaking.

Final point is if you have O/d transmission, I understand that 85W90 is too heavy and that one should use regular 30 weight or 10w30 oil. Never use hypoid oil as it will corrode the brass components in the TR box.

If you want to use something synthetic, then brake fluid is the only thing safe to do...provided you rebuild all the components of the system and flush it thoroughly.

Steven is correct. At least one O/D rebuilder specifies not only straight weight 30W dino oil for the O/D, but also that it be non-detergent.
Rick Orthen

One other point I forgot to add to my view on synthetic oil and O/D, the oil for the tranny can not be of a detergent type as pressures in the o/d unit are very high (~400psi+) and the detergent would cause foaming. Not a good idea!

As I have said several times here before, I have over 64,000 miles on my gearbox with overdrive using 20W50 Valvoline (which is a detergent oil) and have never had a problem over 12 summers. And I drive long trips without any worry. 7220 miles in 2000 to VTR in Oregon, 2,000 miles to Baltimore then 5220 miles to VTR - Colorado in 2001 and now in 2001, 1930 miles to Mid-Ohio and home.

I too thought that the detergent properties would cause the cone clutch in my overdrive to slip, but I got it straight from Ken Gillanders to use the Valvoline 20W50 way back in 1989. And Ken should know.

My overdrive is pressurized at about 325 psi and it snaps in correctly at any rpm and at any speed - cold or hot. I have never had any bad effects that I could tell - like foaming.

Don Elliott, 1958 TR3A with overdrive.
Don Elliott

Since O/D seems to be part of the conversation here,and u seem to put the highest mileage annually of anyone here a question to you please. When going in and out of O/D do you clutch? I was told to do so and I do. When going out of O/D I also give the throttle a little blip. I only use O/D in 4th gear.
Rick Crawford

Detergency--I'm sure there are two things at play here: the foaming issue and the desire to keep debris OUT of suspension to settle in the O/D sumps, not hydraulic passages. Foaming is likely the more important one though.

(PS-I clutch to engage and disengage O/D to minimize shock to the drivetrain).
Rick Orthen

I never clutch when I switch up or down into or out of overdrive. Many's the time I take it up to 5000 rpm in first, then the same in second and when I reach 5000 rpm in second, I flip the little switch I have just next to my first finger of my left hand (TR3A) and the overdrive snaps right in. The tach drops and I take it up to 65 mph in 2nd overdrive without any delay or slip, then into third direct. I don't use third overdrive on accceleration because I feel at that speed I can go to 4th direct.

Downshifting, I do the same thing.

Second and/or third overdrive ratios are great when you want to pass a slower vehicle or a whole line of them. When you see the way is clear, you snap down out of overdrive and out you go, overtaking the whole pack in no time at all.

These ratios are also perfect when climbing Whiteface Mountain (Lake Placid) or in the Rockies when you would be screaming in second direct at 5000 rpm or really lugging it in third at say 3000 rpm climbing those long hills behind a pack of traffic. These intermediate gear ratios with the overdrive really lets your engine sing at the right rpm without straining it or lugging it.

The pressure measured 325 psi about 18,000 miles ago for my overdrive and the cone clutch never slips. In fact the cone clutch is the original one that came with the car 44 years ago.

Hope this helps.

Don Elliott, Original Owner, 1958 TR3A.

Don Elliott

I just thought of another thing on this subject. I never let off the gas petal when I switch up or down into or out of overdrive. Letting up on the gas causes it to clunk and thump into overdrive or out and I don't like that so I don't do it.

Don Elliott
Don Elliott

Geez Don, that's how we all should drive. Guess those were your tail lights is saw. Anyhew, anyone singing through the gears like that in a six routinely?
Rick Orthen

I can't find a retailer for these products in the northeast can you order it direct from the source.
Thanks, Keith
KBD Dixon

65 in 2nd O/D...simply... WOW! No u do not baby her. That is interesting u do not clutch. Since u r original owner, where u told u do not need to clutch when using O/D?
Rick Crawford

Rick - It's not that someone told me that I don't need to clutch when I shift into or out of overdrive, it's just the way it was always done. This is the first time I ever heard of anyone clutching when shifting into or out of O/D. Who was the "expert" that told you to do it ? And what was his reasoning ? Was it a P.O. who knew he had a bad O/D and told the new owner he had to do it. If so, it's a "fix" and not a solution to the problem.

If an O/D cone clutch slips, it means the pump inside the overdrive cannot product enough pressure, then the cone clutch will slip when you click into overdrive. Letting up on the gas pedal a second after switching into O/D will allow it to engage. The reason that a pump might not pump enough pressure was more common on the TR2 O/D's where the two pistons to create the pressure were smaller, hence less pressure was developed and/or if the steel piston rings in these older O/D's were worn or broken.

In about 1957, S/T went to O/D's with larger pistons and rubber O-rings on them to product more pressure and to prevent the slipping with the more powerful engines. If one of these newer O/D's is slipping when you click into O/D, it means that the bores probably need to be honed and new O-rings installed. Pistons and the O-rings are available from Moss and probably others too.

Don Elliott, 1958 TR3A
Don Elliott

I do not wish to name names but u probably know him. He has a brown TR3A with dear skin leather interiour. Member TTC. Probably has parked beside u at Bronte Creek. His reasoning was "ease" on the complete drive system. Before talking with him (he lives about 1/2 mile away), When I first got her back on the road, I did not clutch or let off the gas up or down. It was virtually instantanious in and out of O/D. So it is not a case of slip. When I bought the pile of boxes and one engine one frame and 2 bodies he wanted another $250 for the rebuilt complete tranny with rebuilt O/D. I am glad I bought it. I also say to myself...I would not change gears without clutching so why would I not clutch when changing O/D. It obviously does not do any harm to not clutch as u have done this since new. Sitting here thinking about it, going into O/D will not put strain on anything but coming out of O/D could. There is a sudden increase in engine RPM granted, only about 600 RPM. This is interesting that 2 owners of the same car have 2 different schools of thought.. and when you get right down to it, both are OK. Rick O clutches and his reasoning is same as mine. It would be interesting to see who else out there clutches or does not when using O/D. It appears u can do it either way with no ill effect. It is also interesting to hear u say this is the first u have heard of this clutching thing. U have had your TR3A with O/D a LOT longer than me and my 6. I am glad I asked u...I learned somthing today.
Thanks teach!
The highest I have gone to is 4000RPM second gear (non O/D) ,sorry was looking at the tach not the spedo.
Rick Crawford

Just add my name to the list of satisfied Lucas oil supplement users, chnged oil today and the results were readily evident. A great product for our little cars.I did a 150 miles today very enjoyable except for the smoke clouds our canadian friends are sharing with us her in the northeast.
KBD Dixon

Keith - We up here in Canada drive our TR's without any additives and I'm sorry if the smoke we produce when we drive our cars causes you to have a smoggy day all over the Northeast US. Blame it on Triumph.

Don Elliott
Don Elliott

This thread was discussed between 13/06/2002 and 08/07/2002

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