Cheap vs expensive oil

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Additives are the biggest variable in engine oils, cost and performance wise.
A 5w30 using additives that are created and tested to be an OEM spec normally carry approvals.
Additives that have been made to meet the spec, don't carry the cost- some do have the same performance.

The base oils are typically the same used by blenders to hit the viscometrics for each grade.
Some oils can be used across a range whilst others use specific oils to specific grades.

Group I base oil in the likes of 15w40 mineral oil cost 50p per litre, some pao oils cost £5-6 per litre.
Horses for courses.
 
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Soldato
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Apart from how the oil is made up and the additives, this from opieoils isn't as often posted about:

'Quality control affects the price and quality, the more samples that are tested during production, the more it costs, but the more likely it is to be what it says on the label. Some cheap oils have been found to be well out of grade (one of the worst I've heard of was something that was supposed to be a 5w-40 was actually a 20w-40).

Paying for the name is one way of looking at it, the other way is reassurance due to a trusted brand. Yes, certain branded oils can be expensive, but everyone knows those brands and very few people have ever had problems with them. Some of the smaller brands are less well known and people don't know how good their products will be. That's not to say they won't be fine, but paying an extra few quid for peace of mind can be worth it.

Actual manufacturer approvals can cost a lot of money and that adds to the price of an oil, so a lot of manufacturers sell oils as 'meets the requirements of XXXX' or 'Can be used where XXXX is specified'. You then have to trust the oil manufacturer that the oil is actually suitable for the application, rather than the oil being approved. Don't risk that with cars under warranty, manufacturers will void a warranty if the wrong oil is used. Some dealerships are testing the oil before they look at engine issues now, as if the oil is incorrect, they may be able to get out of doing the work.'
 
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The other thing, it would be more beneficial to replace your oil pump at certain intervals than use an expensive oil.
An oil pump isn't particularly responsible for any measured oil pressure value (unless it is broken), wear on pump impellers has little influence. System oil pressure is mostly determined by the clearances between the cam,crank and bearing shells.
 
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I try to use the best oil I can afford, to help prolong the life of the engine. You can usually get some of the better cheap if you shop around or pick it up when it’s on offer. I use to use the cheapest I could get, as I always use to think it was a big con and all the big brands where just marked up. I use to think the same about fuel.
Now that I work in automotive industry, I have learnt from the guys who have tested all aspects regarding of running the engines using different oils and using different quality fuels. That there is a difference not just in performance, but the it has a large affect on the longevity of the engine. The gains are minimal over the short term, but over the long term you’ll see a difference.
 
Soldato
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I try to use the best oil I can afford, to help prolong the life of the engine. You can usually get some of the better cheap if you shop around or pick it up when it’s on offer. I use to use the cheapest I could get, as I always use to think it was a big con and all the big brands where just marked up. I use to think the same about fuel.
Now that I work in automotive industry, I have learnt from the guys who have tested all aspects regarding of running the engines using different oils and using different quality fuels. That there is a difference not just in performance, but the it has a large affect on the longevity of the engine. The gains are minimal over the short term, but over the long term you’ll see a difference.

Can you ask these people what parts of an engine are lengthened by using expensive oil?
 
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Can you ask these people what parts of an engine are lengthened by using expensive oil?
I can, i doubt the answer will be quick. As the guy I have spoken to at length about this, is still shielding and trying his best to work from home. When I get the chance I will ask.
 
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Well which moving bits, lifters, valves, bearings. Not that many bits.

Pistons, cylinder bores, camshafts and lifters, crankshafts and their bearings, to name a few. Basically anywhere in the engine where two surfaces are interacting continuously.

Edit: Oh and timing chains, too.
 
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Caporegime
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Can you ask these people what parts of an engine are lengthened by using expensive oil?

I don't think any parts get longer due to oil.

Every industry test has a wear limit, some oils just squeak a pass, some pass by large amount. Camshafts last longer as an easy answer.

Here are the ACEA industry requirements for an engine oil, A/B or C categories are light duty so refer to passenger cars and vans, have a read. Theses are the basic requirements, OEMs then build on these:
https://www.acea.be/uploads/news_documents/ACEA_European_oil_sequences_2016.pdf

OEMs have specific requirements within their specifications, timing chain wear, soot handling, global fuel, LSPI, turbo deposits, fuel economy, piston cleanliness, seal and timing belt compatibility etc, all have to be covered by one oil so its like threading a needle, no good using additives that reduce wear but then corrode bearings or rip seals apart for example.

Ask yourself: Do you want an oil that meets the spec of OEM for their engine or do you want one that doesn't? The amount of research and development that goes into oil is significant (€150k in the current most expensive engine test), if the guys think its worth all this effort then who is the consumer to argue. Remember oil its the only part of an engine that touches every part of the engine, it doesn't have one job.

Agree that price is often the biggest factor but I think its worth understanding a bit more rather than just making bold claims that they are all the same.
 
Caporegime
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Manufacturers seem to be using very thin oil in recent years. I assume its for eco stats above longevity reasons :\
Obviously there is a drive to lower emissions hence 1.0 3cyl engine with low viscosity oils. The fines for EU fleet average are absolutely massive.

However to my previous point, the ask on the oil to do more rather than compromise on the engine, hence the development of the Ford 948 specification and why an oil company had the engine prototype 3 yrs before launch.
 
Soldato
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I don't think any parts get longer due to oil.

Every industry test has a wear limit, some oils just squeak a pass, some pass by large amount. Camshafts last longer as an easy answer.

Here are the ACEA industry requirements for an engine oil, A/B or C categories are light duty so refer to passenger cars and vans, have a read. Theses are the basic requirements, OEMs then build on these:
https://www.acea.be/uploads/news_documents/ACEA_European_oil_sequences_2016.pdf

OEMs have specific requirements within their specifications, timing chain wear, soot handling, global fuel, LSPI, turbo deposits, fuel economy, piston cleanliness, seal and timing belt compatibility etc, all have to be covered by one oil so its like threading a needle, no good using additives that reduce wear but then corrode bearings or rip seals apart for example.

Ask yourself: Do you want an oil that meets the spec of OEM for their engine or do you want one that doesn't? The amount of research and development that goes into oil is significant (€150k in the current most expensive engine test), if the guys think its worth all this effort then who is the consumer to argue. Remember oil its the only part of an engine that touches every part of the engine, it doesn't have one job.

Agree that price is often the biggest factor but I think its worth understanding a bit more rather than just making bold claims that they are all the same.

It's a numbers game.

It still doesn't add up though. Average lifespan of a car is 200,000 miles. I wonder how often anything inside the engine gets replaced up to then, I'm guessing cam or crank seals would be the first thing due to heat, maybe piston rings after a lot of miles.

Very rare you would replace a piston, cam, crank. I'm not sure about rocker arms, valves or lifters, and that leaves the main bearings which again I'm pretty sure no matter what oil you use shouldn't need replaced unless your running low on oil.

So all in all it's rare to replace anything in an engine unless it's defective to start or low on oil or some other reason indirectly related to oil.

But people just say, "it's expensive, so my engine will last longer and run faster or smoother" but there's no evidence in that.

As long as your replacing the oil at manufacturers recommendations then that's the important thing.
 
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to Jsmoke:
Not really sure of the point you are making to be honest. The reason engines run so long is due to OEM hardware and engine oil advances.

I don't think we are talking about expensive in the right context here. Oil is relatively cheap, sure there are some bargain oils out there but that's not what we are talking about here as many of those don't meet the specifications we are discussing here? Your last line kind of sums it up from a technical lens, your penultimate line is consumer perception which is what drives thousands of brands in the world, feel good factor.

What car do you drive?
 
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