Engine and Gearbox Oil

[ALISCAR]

The oils listed in the workshop manual are not now available. For the engine (a 1098) I assume a good 20/50 would be best. Do I need to use a "Classic" 20/50 - some of which are designed to protect cork seals in old engines? For the gearbox, it says to use engine oil but I don't imagine a 20/50 would be good. Would a straight 30 grade be right?

[bmcecosse]

It's up to you - this always raises a good 'discussion' - my view is that the Asda/Morrison/Wilko 20W50 is perfectly good enough for a Minor engine - just don't expect it to last for ever... The important thing is to check the filter spring and plate are present under the filter cartridge - many get lost along the way - and then there is NO filtering at all. The gearbox will be fine with 20W50 too, but use SAE30 if you prefer.

[Trickydicky]

Without wanting to hijack the thread, what's the difference in using SAE30 in the gearbox compared to 20W50?
To get back on track I have used this oil for about 4 years now with no problems. http://www.diy.com/departments/carlube- ... 321_BQ.prd

[philthehill]

A chap I used to work with in the BMC garage used to put the straight SAE30 oil drained from Minor gearboxes into a settling tank and when he required engine oil would take a measure off the top layer to use in his Minor traveller. He never had any problems with his traveller engine; so I suppose he could be considered an original eco warrior and recycler

[dalebrignall]

i use the daytona 20/50 from b and q its specked up and fine for a moggy . ive noticed that wilkos do it in a metal can now and its more expensive .

[ALISCAR]

by Trickydicky » Sat Sep 27, 2014 6:28 pm:"Without wanting to hijack the thread, what's the difference in using SAE30 in the gearbox compared to 20W50? "

ALISCAR:
When it is cold, a 20/50 will have the viscosity of a 20 grade oil so thinner than a straight 30 but probably OK. When it is at working temperature, the 20/50 will have the viscosity of a 50 grade which is thicker than a straight 30 grade. I suspect that the gearbox oil runs cooler than the engine oil which would bring the working temperature viscosity of the 20/50 nearer to the straight 30. If the manufacturer recommended a 30 rather than a 40 or 50, I incline to using a modern equivalent that will be nearest to that at working temperature.

That's all!

Nigel

[ssnjimb]

would straight 40 be ok in a worn 1275 gearbox with 80k miles on it,

Jamie

[mogbob]

Jamie
Manufacturers quote oil with a "range " typically 20W50 for a classic car.The engine / gearbox has to operate from a cold start up to hot operating temperature.It has to do so in really cold winters and very hot summer weather.
Is a straight formula going to work as well at the two extremes and everything in between ??
I'm no expert but it doesn't strike me as rocket science.... or will an expert explain the technical reason why a straight oil would be better.
Bob

[ssnjimb]

Hi

im just learning, please excuse my lack of knowledge
jamie

[MarkyB]

Don't worry about it, it's a subject where there are a lot more opinions than facts to base them on.
The main thing is never to run low on oil, get a feeling for how much your car uses and don't ignore it.
The pressure warning light is often a ruined engine light, if it is working properly, so don't use it to decide when to top up the oil.