R230 SL500 Oil selection confusion

[conor1n]

Morning all

Quick one. I bought some Morris oil this morning and was given 5W30 on the basis that that's what was recommended by the Morris system. (I can confirm via Morris website).

I always thought it was 5W40 and that is what the opie oils website says.

Both reputable suppliers in my opinion.

But which is best.

Southern Ireland here....so not a warm climate.

Thank you

 

[DSM10000]

I have never heard of "Morris" oil in the UK, possibly a local brand or supplier?

What is recommended in the vehicle handbook? As long as the oil meets or exceeds the Mercedes specification I cannot see any problems though.

 

[Skd884]

This is correct for your car 5/40

Genuine Mercedes-Benz 5W-40 Engine Oil MB 229.5 Fully Synthetic 20 Litre 20L | eBay

Engine Oil. Transmission Oil. Hydraulic Oil. Classic Oil. Slideway Oil. Compressor Oil. Biodegradable Oil. General Purpose Oil.

www.ebay.co.uk

 

[conor1n]

Yea so I am pretty sure it's 5w40.

I was just wondering what people's thoughts were. Considering Morris oil are a fairly reputable company and all.

 

[Bellow]

Morris have got it wrong (if 5W/40 is indeed the OEM spec).
There are instances where it is acceptable to run with a higher viscosity (if more care is taken during warm-up) but the converse is rarely if ever true. In this case, the 40 is specified to provide the required high speed high temperature shear strength - what stops the oil film from rupturing during episodes of prolonged high load operation - eg, long gradient climbs.
Anyone proposing using a different viscosity to that recommended has to have a very good reason for doing so - and that isn't present here, And that would be for choosing a thicker not thinner oil.

 

[DSM10000]

Yea so I am pretty sure it's 5w40.

I was just wondering what people's thoughts were. Considering Morris oil are a fairly reputable company and all.

The website information etc is not a guarantee of accuracy.

 

[Skd884]

Yea so I am pretty sure it's 5w40.

I was just wondering what people's thoughts were. Considering Morris oil are a fairly reputable company and all.

See my link 20l for £90 - bargain slim.

 

[DavidL]

I tend to stick to mobil 1 in my 113 engines, I imagine they do the correct spec for the 273 too.
However Morris lubricants have been going for years, I used to walk past their factory in Shrewsbury 40 years ago.
Certainly I'd have no issue using their stuff but I'd be inclined to believe MB rather than them for spec.

 

[W1ghty]

Morning all

Quick one. I bought some Morris oil this morning and was given 5W30 on the basis that that's what was recommended by the Morris system. (I can confirm via Morris website).

I always thought it was 5W40 and that is what the opie oils website says.

Both reputable suppliers in my opinion.

But which is best.

Southern Ireland here....so not a warm climate.

Thank you

It will be in the back of the cars glove box manual as well.

 

[ALFAitalia]

It will be in the back of the cars glove box manual as well.

The only problem with using that for reference is that it was correct (hopefully) at time of publication.....but as time moves on and Mercedes get more data they may change specs or the oil maybe be replaced by an upgraded/improved version. So its best to double check elsewhere just to make sure you are giving it the best protection, especially if you have an older car.....if you worry about such things. ALFA are notorious for releasing an engine and specifying one oil....only to change the requirements a couple of years into production. Many cars are now using very thin oils....not so much for protection but to help with emissions.