Thread: Gearbox Oil

Thanks warb,
should add he does not run a mechanical business.
Just uses it on his many bikes, cars, tractors and light machinery engines.
So using your technical knowledge, to run the available Castrol vmx 80w mentioned earlier and say, 10 mils of the Lucas ' Honey ' would we then be able to achieve something like the original 90 ????
This is a series forum, yet only a small few have posted.
What is everyone else using in there series gearbox.
Love to hear from a few more of you.
Then maybe the powers to b,e could make a sticky of the helpful bits of the thread.
Or are we just re-inventing the wheel !!!!
thanks

whitehillbilly

I'm using a 75W/90 in all mine without any problems to date.
I believe it's a synthetic base.

The Lucas oil stabiliser was possibly made by the blender I deal with, they have a similar product.
It's like treacle and should only be added to hot oil.
Reading the list of things it does makes me think it's distilled from snake oil.

Colin

Originally Posted by whitehillbilly64

This is a series forum, yet only a small few have posted.
What is everyone else using in there series gearbox.
Love to hear from a few more of you.

This conversation tends to be a bit like tossing the proverbial hand grenade into the ants nest mate, maybe this is why people are sensibly quiet

My Series 1 is a long way from being on the road so I hadn't thought too much about it. However, it never have occurred to me to use anything but mineral oils of the specified grade with frequent and regular changes, just as specified. I've listened to the synthetic vs mineral oil too often on too many forums relating to old vehicles to ignore the wise old heads who all point back to what the factory said to use.

As a reference, the people who developed the engine in my MG ZR were adamant that you use a semi-synthetic oil of a particular grade. That same engine was used in the Freelander, which has a poor reputation on this forum... and people insist on using synthetic, not the semi-synthetic specified. I know from UK forums where my MG is common (they only bought 48 to Oz so there's no discussion here), that synthetic oils, failure to look after the cooling system and failing to repair the head gasket properly all lead to the sort of issues the Freelander people talk about. Again, listen to the people who made the thing in the first place.

So my thought with my Land was to always use good quality mineral oils of the grade specified and to change them regularly.

However, I haven't tried to buy said oils, I just assumed they were available and maybe that's where I'm going to run into trouble.

I've also noted that individuals work out what suits them and their vehicle and provided you change fluids often and regularly, almost anything works and so I'm not going to argue with anyone's choice.

Originally Posted by gromit

I'm using a 75W/90 in all mine without any problems to date.
I believe it's a synthetic base.

The Lucas oil stabiliser was possibly made by the blender I deal with, they have a similar product.
It's like treacle and should only be added to hot oil.
Reading the list of things it does makes me think it's distilled from snake oil.

Colin

its a teflon base thing from memory, or at least it performs the same function. it gets on the hot metal bits and then sticks to it while at the same time increasing the surface tension of the oil its put into without drasitcally effecting the overall viscosity...

hows that work? roughly...

all fluids have a surface tension, for the purpose of this discussion think of it as a balloon full of water. If you use a very thin balloon you have a very pliable skin that deforms and shapes to whatever it sits on but the skin is easily penetrated.

if you use a thicker balloon the water is still the same water but the skin is harder to deform and its harder to penetrate.

There are pros and cons to each.

Originally Posted by whitehillbilly64

So using your technical knowledge, to run the available Castrol vmx 80w mentioned earlier and say, 10 mils of the Lucas ' Honey ' would we then be able to achieve something like the original 90 ????

From purely a viscosity standpoint, using a thicker oil whether the Lucas product or anything else, will increase the viscosity. The problem is that it also dilutes the other additives from the concentration that the manufacturer has used. So you have a thicker oil, but with reduced additive concentration. Using Penrite Mild EP also gives a higher viscosity, but with the additive concentration that the oil manufacturer specified.

Originally Posted by crackers

However, I haven't tried to buy said oils, I just assumed they were available and maybe that's where I'm going to run into trouble.

Nailed it! You can no longer buy straight EP90. You can buy 80W/90, which in theory has the same SAE90 rating at high temperatures. The problem is that SAE90 covers a range of viscosities and to get the 80W rating when the oil is cold the manufacturers tend to steer to the lower end of the SAE90 rating. It's not an enormous issue (no issue at all for modern cars!), but when the gearboxes are old and worn a bit more viscosity is better! The other issue is the GL4/GL5 change. Opinion is divided as to whether the GL5 additives will cause damage..........

Originally Posted by Blknight.aus

its a teflon base thing from memory, or at least it performs the same function.

You might be thinking of the moly type additives that deposit a slippery coating on the metal? The Lucas product is "100% petroleum based" so no moly or teflon. As often is the case with these products, it gives no sensible explanation of how it is supposed to work, but the TDS shows a very high viscosity so I'm guessing it just thickens the oil.

"Oils" work in 3 ways. Initially the film of oil lubricates the surfaces that are in contact. When the pressure between the surfaces overcomes the film of oil, friction modifiers (if present in the oil) take over. Lastly there are the extreme pressure "EP" additives (hence EP90, SAE90EP etc.) that form protective coatings on the gears - they are also known as anti-wear additives. The problem is that I don't recall friction modifiers or EP additives being petroleum based, which would mean that adding the Lucas product reduces the concentration of EP additives, and relies solely on the increased viscosity of the oil to maintain the "oil film" between the gears. But because they don't provide any real technical information, that's just a guess.

What really made me wonder is that apart from increasing performance, saving fuel, making the oil last longer and making the gearbox last longer, it is also claimed to "stop oil leaks". Really clever stuff!!

Several other 'oil stabilisers' out there.


MOREY?S? HEAVY DUTY OIL STABILIZER
USED AS DIRECTED, IS PROVEN TO:
 Reduce operating temperature in engines, gearboxes,
differentials & Hydraulics
 Stop piston wash during cold weather idling
 Eliminate dry starts ? increased engine and gear life
 Improve and sustain oil pressure
 Protect against high temperature viscosity loss
 Insure against oil breakdown in case of sudden overheating
 Reduce oil consumption
 Extend life of regular oil in all applications
 Smooth & cool hydraulic operations
 Reduce noise in transmissions & differentials
 Improve cold temperature starting: to minus 40OC
 Reduce heat, slip, grab, and leaks in automatic
transmissions
 Stop blow-by. Horsepower is increased
 Have higher index to resist thickening or thinning of
oils
 Improve engine & component cleanliness
 Improve rust & corrosion protection
 Reduce seal leakage
 Improve compression & fuel economy
 Reduce emissions


Flashlube Heavy Duty Oil Stabiliser: Flashlube fuel additives Synthetic lubricants for the automotive industry - Genuine Flashlube


Don't rebuild your worn engine, just run on oil stabiliser........



Colin

With enough additives in the fuel and oil, plus magnets on the petrol pipe, metal marbles in the fuel tank and a spiral-air-whizzer-doo-dad in the air filter hose, my 50 year old 2L engine will last forever, produce 500bhp and use less fuel than a Prius!!

Originally Posted by Warb

With enough additives in the fuel and oil, plus magnets on the petrol pipe, metal marbles in the fuel tank and a spiral-air-whizzer-doo-dad in the air filter hose, my 50 year old 2L engine will last forever, produce 500bhp and use less fuel than a Prius!!

Runs on vodka does it?
Oh, that's the driver