Oil & Cold Starts - Good Advice from Opie Oils

[oilman]

At this time of year, it’s beneficial to use an oil that has good cold start flow properties as it will get to the parts of the engine that need it far more quickly when you turn the key on those sub zero mornings.

The "w" number which means winter is the key here and the lower it is the better cold start performance the oil will have.

A 15w or 20w rated oil will struggle to get around the engine in very cold temps and we would strongly recommend using a 10w, 5w or 0w for better cold start performance.

It is a fact that around 90% of all engine wear occurs on cold start because the oil is at its thickest. The colder it gets the thicker the oil becomes and this affects the rate of flow which affects the rate of wear.

These numbers help to explain the oils thickness and therefore cold flow performance at various temperatures.

Grade.................At 0C.................At 10C..............At 100C

0W/20.............328.6cSt...............180.8cSt.... ........9cSt

5W/40.............811.4cSt...............421.4cSt.... ........14cSt

10W/50............1039cSt...............538.9cSt...... ......18cSt

15W/50.............1376cSt..............674.7cSt...... ......18cSt

20W/50.............2305cSt...............1015cSt...... ......18cSt

Centistokes (cst) is the measure of a fluid's resistance to flow (viscosity). It is calculated in terms of the time required for a standard quantity of fluid at a certain temperature to flow through a standard orifice. The higher the value, the thicker the oil.

Winters in the UK are fortunately not too cold but, below zero temperatures are regular features in some parts of the country.

Compare the thickness of the oil at 0degC and 100degC and you will see the big difference.

Just something to consider on those frosty mornings.

The Opieoils Team.

[Phil Payne]

Originally Posted by oilman

A 15w or 20w rated oil will struggle to get around the engine in very cold temps and we would strongly recommend using a 10w, 5w or 0w for better cold start performance.

And I strongly recommend NOT doing so in any ur-quattro engine.

Who are these dorks?

[LYT4X]

Originally Posted by Phil Payne

Who are these dorks?

This is the new breed of salesperson using Internet fora as their campaign medium. I see Opieoils on many different places dishing out the same regurgitated guff. I don't suppose you can blame the specific poster as he probably wouldn't know the difference between SAE and API if it was poured into his coffee cup.

However, whilst most of it holds true for a modern car with a new engine, it is, as you say, poor advice for a 20/30yo 5-pot turbo.

[Isimmo]

Originally Posted by LYT4X

poor advice for a 20/30yo 5-pot turbo.

Indeed, some of the shell damage in ours is probably through too much Synta Gold type viscosity over the years.

I think we'll be using this.

[PeterB]

Originally Posted by Isimmo

....I think we'll be using this.

That's what the MB is currently running on, and very nicely too I may add!
It seems a 10W-50 or 15w-50 grade decent synthetic is ideal for the ur's.

[oilman]

Originally Posted by Phil Payne

And I strongly recommend NOT doing so in any ur-quattro engine.

Who are these dorks?

Ok, I am always keen. Why do you advise against using a 10w? I can understand the fear of 5w and 0w oils. Also is the UR Quatro the only classic Audi?

Cheers.
Guy.

[oilman]

Originally Posted by LYT4X

This is the new breed of salesperson using Internet fora as their campaign medium. I see Opieoils on many different places dishing out the same regurgitated guff. I don't suppose you can blame the specific poster as he probably wouldn't know the difference between SAE and API if it was poured into his coffee cup.

However, whilst most of it holds true for a modern car with a new engine, it is, as you say, poor advice for a 20/30yo 5-pot turbo.

New? I have been on forums for over 6 years now discussing and selling oils. I would say thats more like established.

This information is fact, and does not just apply to new engines as it is relevent to many classic cars and some vintage, I was not aware the 5 pot turbo was the only classic Audi out there.

As for not knowing the differnce between API and ACEA... Get real.

As I said in the other post, I am keen to discus. Please give me some facts as to why 10w is not suitable in a 20-30yo 5pot turbo? As I have many customers running these engines (most running 10w-50) and I may need to get them to change their oil asap based on the advice and facts you can offer me.

Cheers

Guy.

[Tanni]

Now I totally lost the clue?

I still now very, very, very little about cars in general but I can already now feel that my car needs a lot more time warming up in the morning. Is that simply because of the engine oil being colder?

And what should I do then?

[rich.r]

Originally Posted by Tanni

Now I totally lost the clue?

I still now very, very, very little about cars in general but I can already now feel that my car needs a lot more time warming up in the morning. Is that simply because of the engine oil being colder?

And what should I do then?

the ambient temperature will affect warm up time

just use the oil as directed in your hand book and you wont go far wrong

[oilman]

Originally Posted by Tanni

Now I totally lost the clue?

I still now very, very, very little about cars in general but I can already now feel that my car needs a lot more time warming up in the morning. Is that simply because of the engine oil being colder?

And what should I do then?

As said above, ambient temps effect warm up time as the colder it gets the more viscous the oil becomes, the longer it takes to flow around the engine on start up and the longer it takes to warm up.

The table in my first posts shows how oils are effected by cold temps, and this is with a multigrade that was designed to combat cold temps. Imagine what iit was like when we are all using monograde SAE30 and SAE40 oils.

Use the correct grade and all will be fine. What oil are you currently using?

Cheers

Guy