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Triumph TR6 - synthetic oil ??

Hi folks,
I just wanted to hear everyones thoughts on the lube of choice (keep it clean)I am thinking of going synthetic is this a good thing for my 73 TR?

I have used Castrol 20W50 in my TR3A engine for the last 5 years. For 9 years before that I was using Castrol 10W30. I will stick to the 20W50. I change my oil filter and oil every 3,000 miles. In the last 14 years, I driven over 78,000 miles with no problems using this non-synthetic oil.

"If it ain't broke, why try to fix it ?"

Don Elliott, Original Owner, 1958 TR3A
Don Elliott

I'm sure the new synthectic oils would give you
sufficient lubrication but they are really designed
for newer engines that are tighter in tolerances and
run hoter than the Triumph engine.
Synthectics are very expensive and personally
I think you should use the older tech oils and spend
that extra money on something else for your baby.
She will always need something.
By the way, what happened when you took the car to
JD Auto? Did Joe fix her up?
Christopher Trace

I think there was something on explaining the specifications between oil brands, including the synthetics. The specs on the synthetics were more impressive, but I've had a problem justifying the cost.

Anyone know what's going on with The website's been inaccessible for at least a couple of weeks.

Mark Hauser

I, like Don E; run Castrol 20W/50. I do not put as many miles on my 6 like Don puts on his 3:)
Keep in mind, us TR owners tend to baby our little cars and oil changes are usually more frequent and I would say we all do our own changes.
One thing for sure. Do not put synthetic in the tranny if you have OD.
One other word of caution. Be carefull on topping/filling up your brake and clutch reservoirs. My point is if you have DOT 4 (or older DOT 3) currently in there, you do not want to add DOT 5 ( the synthetic version) as a top up. This is a NO NO!!
DOT 5 is NOT compatable with DOT 4/3. I would think ( from what you have said about your 6 and the DPO) that currently you are DOT 4. The recomendation for DOT 4 is CASTROL LMX DOT 4.

OK so I can already hear your question:)
There are many past threads that will help you determine if you are DOT 4 or 5. Happy reading.

Yes, what did JD have to say? We are all very curious!! Remember, we are here to help:)
Rick C
Rick Crawford


Now that I have my oil drips stopped, I'm going with Shell's syn Rotella ($13/gallon at Wal Mart) at my next change. While the dino users who have frequent oil change intervals (OCI's) are perfectly fine, I have a preference for the engineered nature of syn oils. [I run Mobil 1 exclusively in my other 2 vehicles with extended 1 year/10K mile OCI's.]

I've posted this link before, but it's worth a read for an oil & filter education:

Rick O.
Rick Orthen

Boy oh boy,...
it seems black or grey area. Some of you love the new synth oils others so no way (?????) Rick thanks for asking about JD Auto, with spring here he was so busy in the past few weeks with all kinds of Brit cars I needed an appointment to bring my TR there. It was finaly delivered yesterday morn (4/17/04) the waiting game. I was thinking of talking to him further at the Ancaster swap meet but It looks like heavy rain as I type.

If you want to use syn oil, do so. It will not harm the engine. It is just a lot more expensive up here in goose land....$8.00+ per quart... mind you a Canadian quart:). The do not use syn. oil in a OD tranny still stands though.
We look forward to what JD says.
Rick C
Rick Crawford

NEVER USE SYNTHETIC OIL IN AN OVERDRIVE TRANSMISSION?......and I thought it was because we are down-side-up that we do things frack to bunt!

Here is some food for thought.

The word synthetic = man made? ... true, but NOT in the case of oils!!!

Motor industry synthetic oils are actually mineral based oils which have had "man-made" (meaning "not natural") molecular separation technology applied to them which creates the base stocks used for all synthetic oils (except Mobil's jet turbine oil which is from palm trees).

The "synthetic oil" companies use different proportions of base stocks (di-ester and pao-ester) to which they add their own secret herbs and spices, marketing and charging accordingly.
(di- & pao's were originally extracted from waste products in the oil process and now it is used for their premium oil stocks!)

Mobil extract a 'polyol-ester' base stock for aviation but will not sell to anyone else, so you and I can't get access to it - why? - too much profit lost and who want's to see the planet covered with palm trees anyway.

Redline is the only company that adds polyol-ester to its "synthetic" transmission oils. The moleclar characteristics of polyol-esters (apart from having an extra atom - and we all need lots of them!) is that they give better shear, heat dissipation and load resistance - hence the use in aviation.

This gives their oil (particularly the MT-90), the appropriate characteristics for use in wet clutch overdrives (with a flow rate similar to a 30w engine oil).

I use Redline MT-90 in the tranny with J type O/D and find it fantastic. It is a 75W90 weight and feels very light, synchro meshing is superb and there is no slip in the O/D, even engaging without the clutch
at 5000rpm in 3rd (150bhp+).

In summary - generally, a good mineral oil is better than a poor "synthetic oil" for engines, but there is also a synthetic for O/D gearboxes if you want it.

I have no interest in the company, I just tried it and it works for me.

Roger H

Only going by what I have seen many people posting about do not use syn in OD tranny.
Simply put, if I read several people saying that it causes the OD to slip in their TRs then why would I go out and see if it does slip in mine ( A type).

Quite frankly, I would rather use a syn in the tranny. This is interesting to hear. Is there a major difference between an A and J type OD that would allow syn oil in a J type?

Maybe Redline MT 90 is the ONLY syn oil that WILL work????
Maybe an e-mail to is in order to their Tech dept.
Thanks for the info Roger
Remember.... green side up:)
Rick C
Rick Crawford

Hi Rick

I was just adding a bit of oil to the fire ;)

I see no reason that MT-90 won't work in 'A' units if it works in the 'J's. They are both wet clutch types that require an oil that is good in shear.

As far as I have been able to find out, the Redline MT-90 has been formulated specifically to have high shear properties. I have had a couple of serious talks with the Redline distributor here and my inderstanding is that they are the only company to market gearbox oil with the required polyol-esters (heat,shear & load benefits). Other marques here (MG's, Morgans running OD's) also use it without any bad reports (that I'm aware of) although I haven't fully investigated other companys' products as I tried the Redline and it works.

My tranny has been rebuilt to min. tolerances. It could be that a worn unit may not be as suitable.

If you decide to try it, please post back with your opinion.

Roger H

Don't get me wrong, it's not that I don't like synthectic oils, they are great. They are just very expensive, and your engine will not be any better off
because of them.
Christopher Trace

Roger & Rick - The warning about not using synthetic oil in a gearbox came from several TR racers who were using it and found that on deceleration, the synchros in the gearbox were so slippery because of the ultra slippery nature of the synthetic oil - that it would slip out of gear into neutral. One TR racer demolished his TR this way - but he survived. All the others discussed the problem together with the surviving driver of the crashed TR and they all reported the same thing happening. Those who had the problem switched back to the oil they had been using and the "falling out of gear" disappeared right away.

Don Elliott, 1958 TR3A
Don Elliott

Don - Interesting that it was a gearbox failure rather than an overdrive problem - (maybe they should have used Redline MT-90!!!!)

As the say Oils ain't oils! - check this - particularly wrt viscosity and synchro

PS My TR box has ever jumped out of gear!

Roger H

HA - goose swallowed the N !!!

(The PS should read NEVER !!!)
Roger H

I have not tried synthetic but use 20/50. I remember reading something from Crower cam company (I think)they do not recommend using synthetic oil for cars with solid lifters. Cant remember why.

Ken Gillanders in California was the person Don refers to: I think the problem was transmissions popping into neutral from 2nd. under very hard braking, not something you could likely duplicate in street driving.

I have been using 2 litres of synthetic (Castrol Syntec) blended with the Castrol 20/50 . I am hoping to get the cushionig effect of the heavier, conventional oil and the lower friction and higher film strength of the synthetic. The other benefit is synthetic doesn't drip off as easily so when you start up after a few weeks of just sitting you still have some protection.

I am hoping by sticking to one brand the additive packages will be compatible; not very scientific, but an ideal compromise if you can't make up your mind on this issue!
Happy TRails, Simon.
Simon Rasmussen

I heard many years ago that the synthetics were so good that you simply didn't need 4 or 5 litres to get the benifits, that 1 litre had enough to make your dino
oil superb. Since then I have been doing my own blending. Keeping faithful to the company for additives
I've been adding 1 litre of syn to every 3-4 litres of dino. I don't race so all I can say is I think it's
better. I can't report better milelage or less oil
consuption cause I don't record those things. But it does make me feel better about it. I suspect that unless you are a hard racer or a million miler that most "improvements" go unnoticed.
And that goes for that whole isle of car products at the local store,"tuneup in a can" for lack of a better name.
Kind of like buying treats for your cat or dog.
They make you feel good but don't expect any thanks
from your pets or cars.
P.S. Sometimes you just have to rant.
Christopher Trace

Call me stupid but what is a dino?
Not sure here, do you have a TR gear box..Yes/No?..OD??
Rick C
Rick Crawford

Hey, Rick. Dino as in good old fashioned "dinosaur oil".

Brent B

I agree completely, Chris, I am sure with the low annual mileages we do noone will know for sure, but it oes feel good to pamper the car!
Simon Rasmussen

Rick - yep - TR6 4 speed (bronze bushings in lieu of needle rollers) J type O/D (all rebuilt to min spec tolerances).

I use the synthetic in the box as I feel I get the value out of it as oil changes are less frequent. I stick with mineral based for the engine as it is changed at least 4 times a year (each season and before / after occasional track work) Filter is changed at each oil change (a small but worthwhile investment).

Roger H

Sorry. The question was for Chris. But interesting you do not have a slipping or pop out problem. I like the idea of mixing "dino" with syn. (dino eh?...even an old F*#$ can learn something every day:)
Simon, it sounds like you do this mix for the engine and I know you race. Do you also do the mix for the tranny?
Rick C
Rick Crawford

Rick, I have only done a few track days the last couple of years and about 5 Solo 1 events per year before that, so am not a hardcore racer.

Like Roger in Oz, I change the oil after every track event in the belief that high revs and temperatures somehow beat the viscosity out of the oil; this is probably not true but it makes me feel better!

I have overdrive, and understand the o/d unit likes 20/50 motor oil while the gearbox likes 80/90 gear oil, but since they share a common supply I have been blending this too, sometimes use 75/90 synthetic gear oil. I change this every year or if I do a long highway run at high speed because this makes the box hot. I check for " glinty" particles, so gar so good.
I also top up the diff annually, but its a pain to drain by suction. I thought about drilling a hole in the case and tapping it for a drain plug.
Simon Rasmussen

sorry Rick - I've been called a few things and respond to just about any name these days!

Personally, I'm not keen on the idea of a 'home brew' when it comes to oils. Synthetics ARE a blend of mineral oils anyway, done and tested by the company. I would be a little nervous of upsetting the balance of additives and comprimising the quality of the base stocks that you pay so much for with the better quality syns. It IS possible to get the correct weight and viscosity from synthetics for virtually any particular requirement.

(I think I've said enough now - I'll shut up!!)
Roger H

This thread was discussed between 18/04/2004 and 27/04/2004

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