Oil labelling explained

[copperbollock]

Evening all, took the old man's Merc out for a run tonight and I need to sort the diff and gearbox oil out. It's been laid up for four years so it needs doing. The dif has started to whine and the there's no kickdown.
What oil and how much if needed for the dif and auto box on a 1993 250D?

 

[oilman]

This one meets the spec for the diff

http://www.opieoils.co.uk/c-723-mb-2350.aspx

And these are ideal for the ATF

http://www.opieoils.co.uk/c-923-mb-2366.aspx

Cheers

Tim

 

[zars]

W203 C180K Avantgarde SE Engine Oil

Hi chaps

Need to top up my W203 C180K and have been browsing this thread with interest (great info). Is the following suitable:

http://www.opieoils.co.uk/p-68924-f...ynthetic-engine-oil-for-bmw-amg-mercedes.aspx

Also what's the best viscosity for the UK in general?

Daily journey is a round trip of 10 miles in stop start traffic with the ocassional blast (sort of) on the A roads. Killing fuel economy unfortunately (230 miles from a full tank)

Cheers

 

[oilman]

Hi

Yes, that is suitable, as are all the ones via the link below

http://www.opieoils.co.uk/c-716-mercedes-engine-oil.aspx

Technically, any of the 0w-30, 5w-30, 0w-40, 5w-40 or 10w-40s are fine, but generally I wouldn't go for the 10w as you lose cold start protection. If the car doesn't burn much oil, a 30 will help (marginally) with fuel economy, but if it does burn oil, a 40 should slow the oil consumption.

Cheers

Tim

 

[zars]

Many thanks Tim

 

[oilman]

Thanks for the order.

Cheers

Tim

 

[R W]

Tim.
I am in the process of buying a 320cdi,2007, with DPF. The car will be used in Kyrgyzstan where winter temperatured can be -25,-30decC. Summer temperatures reach + 40degC so we have extremes of temperature. Most DPF oil seems to be 5w-30w, would it be better using a 0w-30w or 0w-40w considering the cold winter climate here.
Thanks in advance.

 

[oilman]

Difficult one, if you dont use an oil suitable for DPF you could end up with all sorts of problems. 5w should be OK.

Cheers

Guy

 

[R W]

Guy.
Thanks for your reply, I found a temperature range chart for oils on a google search & it seemed to indicate 5w was ok to use to temps of -30degC. So maybe it would be OK.
I would prefer the 0w but if its not available then I have no choice in the matter.

 

[Tju]

Guy, Your help and/or advice would be appreciated. Would a lesser known (Cheaper) brand of MB 229.5 spec oil, do the same job as a more well known (More Expensive) brand of MB 229.5?

Regards,

Terry.

 

[oilman]

Basic oils that say they meet the spec may only claim to - they often say 'meets the requirements of' rather than 'approved'. That means that the oil only claims to be suitable, rather than is suitable.

Also there is meeting the spec and exceeding the spec. Cheaper oils will just meet the spec, the use of additives needed for specifications are expensive and using less cuts the price. Then you get oils like Castrol Edge 5w-30 and Mobil ESP which are approved for many specifications. That means they will exceed many of them in certain areas.

Also, some of the approved oils will be PAO (genuine lab made synthetics) and others will be hydrocracked (modified and refined mineral oil). PAO oils are a step up in quality than a hydrocracked one and will give better protection.

Cheers

Tim

 

[cutaresku]

Where can I identify country codes? I can only notice "EU" as origin. Assume first 2 out of the long number should tell "made in...".
For instance, Mobil 1 ESP 5w30, where should be made?
Thanks.

 

[oilman]

They can be made in variouse countries, to the same recipie. There is nothing on the can to tell you where, or who made it.

Cheers

Guy

 

[chizzel89]

Why are Comma Oils cheaper than other brands even though they claim to meet the same specs? Does it have anything to do with them being owned by Exxon or are the oils poor quality?

I only ask, as I recently changed the ATF and filter on my 722.6 NAG 1 transmission, and used their MV ATF fluid at it claims to meet MB236.12 which would make it better than the fluid the transmission was originally filled with. Will it actually meet that spec or are they telling porkies which could cause expensive problems?
I change the ATF and the filter every 25k miles and drive very gently from cold, so I thought I would be wasting money using a top quality fluid and changing it that often? I'm having second thoughts now though...

 

[oilman]

Yep it is all in the wording.

It says recommended for use in applications requiring... That is quite different from being approved http://www.commaoil.co.uk/productsguide/view/6/180 But not uncommon practice amongst oil manufaturers/blenders as purchasing an approval can be very expensive and will put the price of the oil up. Comma is cheaper as it is made to a lower cost, base stock, additive packs etc.

Cheers

Guy

 

[JimM]

There is conflicting explanation on the web about Viscosity.

I'm an old bloke and thought I knew that the lower the number the thicker the oil at a given temperature, so this is why a 10W40 oil which has a viscosity of 40 at 100C and a viscosity of 10 at 0C or lower, is thinner than a 5W30 oil at both ends of the scale, 100C and 0C or lower (the W temperature test is varying from -5C to -30C according to the W rating, rather than being a measurement at 0C).

Because of these varying lower-scale test temperatures, it can appear that the same oil will give a 0W at -30 and rising through all the W grades to 25W at -5C. But we know this is not the case.

The lower the number, the slower the flow because the oil is thicker than an oil with a higher number for that given temperature.

And lower SAE number oils are better gap-fillers so they are better for older engines which have larger tolerances in main-end bearings and piston rings for example, or for worn engines which may have larger main-end bearing and piston-ring gaps, for example an engine that would normally use 10W40 can be quietened and smoke a bit less by using 5W30 or 0W30 oil.

I have also found charts showing that oil flow is given in centistokes, or mm2/second, and these match my understanding too.

Here's one example: http://www.upmpg.com/tech_articles/motoroil_viscosity/

However! In many cases the worded description of viscosity, is the reverse! That the higher the number, the thicker the oil!

To me this does not compute, and doesn't match the chart either, because we know for sure that oil thickens when it is cooled, and thins when it is heated, so the oil flow increases with the SAE number at a particular temperature, so that a 10W30 oil flows at 4.1mm2/s (Winter) and 9.3-12.5 mm2/sec at 100C, whereas a 5W30 oil flows at 3.8m2/sec at the lower temp and at 9.3-12.5 mm2/sec at 100C. This computes.

My apologies if this is already answered, there is far too much to read through using the search but I did give it a go. Would you give me a link to a correct explanation?

 

[oilman]

Hi

You've been looking at it incorrectly, a higher number relating to viscosity means the oil is thicker. This article explains it

http://www.opieoils.co.uk/pdfs/tech-articles/Engine-Oil-Viscosity.pdf

Cheers

Tim

 

[JimM]

Thank you Tim.

Got it, having read your link.

So for worn engines I should have used say 15W, not 0W nor 5W oil!

Ah, well, in those days there wasn't much damage to be done by oil that wasn't already done to the engine, so it's possible that just the fresh oil quietened the engine - or maybe the additive too, Slick-50!

Hehe - those were the days!

An old slicker than slick-50 pal put in some EP-90 gear oil to silence his knocking big-ends and a handful of sawdust in his rear axle to stop that howling, then sold the car. Somehow it never came back. I would never buy a car from him!

 

[oilman]

I wouldn't use oil additives, they can cause some real problems.

http://www.opieoils.co.uk/pdfs/tech-articles/Aftermarket-oil-additives.pdf

Cheers

Tim

 

[EmilysDad]

Actually, many people nowadays they don't really understand what the particular things they going to use especially on the kind of oil or brake fluid. They usually use the thing that can think its easy but they don't really understand what the real use and what the function if they are going to use this kind of fluid. Moreover to this, try to search or make an information about this matter so that you will notify what is the fluid you are going to use for your car.

Que?
Can you translate that to proper English like wot we speeks please?