DELETED_5350
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Just as well I change my oil every 6000 miles not 20,000 then
Another myth. This isnt aimed at you but more of a General comment. Changing poor oil more frequently than good oil is not better for the engine
Simon, Castrol recommend EDGE 5W-40 (a) or Magnatec 10W-40 A3/B4 for my engine.
Considering I've just had the engine rebuilt is it worth using the Edge over the Magnatec? Would it be better for the health of the engine or is the engine not 'new enough' (Made in the mid 90's) to make use of the Edge and paying twice the price is not worth it?
Considering I've just had the engine rebuilt is it worth using the Edge over the Magnatec? Would it be better for the health of the engine or is the engine not 'new enough' (Made in the mid 90's) to make use of the Edge and paying twice the price is not worth it?
1. Bearing is a very generic term, there are big end bearings, main bearings which generate their own oil pressure to support the load from the pistons via conrods. This relies on the oil being supplied at the right flow rate and having the correct properties under pressure, if not the bearings will pick up (spun bearings), this is further complicated when you start introducing fuel and water into the sump thinning the oil out causing break down under high cylinder BMEP (torques)
Small end bearings are very much a metal on metal lubricant regime (Known as boundary lubrication). Camshafts and camshaft bearings also are under massive pressure where oil films break down.
You seem to have not even thought about :
Detergent performance, keeping engines clean and neutralising acids
Dispersants for controlling soot and sludge
Oxidation performance of the base oils /anti oxidants for controlling
Viscosity growth / oil consumption due to light end volatilty.
Shear stability of viscosity modifiers to avoid viscosity drop.
Pistons and piston rings, at ring reversal points there is metal to metal contact, turbo charger bearings at start up, engines with cooler temperature running where normal ZDDPs dont work. Cylinder liner wear needs to be controlled - need to stay round and polish free to maximise the performance (and emissions) of the engine, as well as avoid high oil consumption for the driver.
This isnt even going into the details of each industry and OEM test. Here you can have oils that just pass a 120 micron wear limit claim the same spec as the oils that get <10 microns. Certainly not the same performance despite the same basic spec.
2 OEMs have specifications for a reason, put a non VW 505 01 oil in an engine with Unit injectors and pretty soon you will have no camshaft left - I have seen it. Put the wrong viscosity in a high tuned engine and the big end bearings spin. Put the wrong oil in another car and the timing chain wears out. Put the wrong oil in another and the yellow metals corrode.
3 Oils of the same type is ok - but my definition of type in the additive technology used, sometimes you can mix oils which causes a large increase in the viscosity at cold. Salcylates or phenate soap in the oil? No consumer can tell this. Whilst there are tests to ensure oils are compatibile it doesnt mean you are getting the best from the oil from mixing them.
One example - High Ash 5W-30 cant be mixed with a mid ash 5W-30, they could carry similar specs (this is being driven out of the market by ACEA) but the high ash oils are not suitable for diesels with DPFs.
Another one - you can have two API SN oils of a 5W-40 with very different specification profiles, one suitable for a BMW, the other not but by assuming its fine to mix 5W-40s you could run into issues on N42 Valvetronic engines.
I cant really comment for the OP as I dont know what oil he bought, what specs or brand.
PS - none of this is cut and paste so please accept apologises for typos
Specifications have minimum limits, you can scrape passes on oils that arent even the oils you sell but support the oils on the shelf. Or you can pass them by a large amount. The real challenge - evident in this thread - is education customers on the differences and building marketing storys they can understand.
Crikey, thank god I don't have anything to do with modern cars anymore
I know how all the bearings work, I spent a good chunk of the last 30 years building engines, and rebuilding those that had spun a shell.
I stand corrected in every way with regard to modern vehicles, I can only assume this kind of sophistication and problems associated with newer technology is only going to get worse. Thankfully in my 17 year old car, I mainly have to look after the turbo plus mains and big ends, for that I use Millers CFS
Yes I know about detergents, oxidisation, acids from combustion, and cylinder wear, but like I said, where oils meet the manufacturer specs they should cope with all of this. Obviously in modern VAG TFSI and other sophisticated low emission, high performance engines things have got more complicated especially in the search for longer and longer service intervals. Seeing the state that some TFSI VAG engines get in just through removal of the petrol flow over the valves, it is understandable how important the role of oil has become in these engines.
It's not only the wrong viscosity oil that can spin a bearing, driving hard from cold (which I see people doing every day /facepalm) my wife's company car has developed a nasty turbo whine, mainly down to how she drives it imho.
Fuel and water in the oil should be limited if the car is regularly driven for longer journeys (the same way as you keep a DPF clean), allowing it to get properly warmed up for a while, if you just do lots of short journeys it is hard to burn this off and as a result you are gonna thin the oil, emulsify it and often leave it with high acid content (which eats alloy, including bearing shells). I am pretty sure the modern cars variable service intervals are mostly affected by the type of driving you do above all else.
TBH I had allowed for all of which you mention on an older ST200, if the question had been about a modern TFSI or Diseasal I wouldn't have commented at all, as those engines seem to be way too fussy about almost everything you put in them (my old boss's boss killed his Mk5 GTI turbocharger and cylinder head using the wrong oil to top up, I don't know the specifics), and what I know about modern BMW engines can be written on a postage stamp, come to think of it the same probably applies to any engine first made in the last 10 years
I would assume that almost all manufacturers will go down similar routes longer term if they aren't already, before they are forced into electric vehicles.But anyway, thanks for making a constructive post pointing out some of the errors of my ways.
Soldato
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I bet most engines would be fine on 10w40 unless thrashed to within an inch of their life.
My idiot lodger insists on spending out for 5w30 in his 160,000 Vectra GSi even though there are clouds of blue smoke and he uses a litre every 400 miles. I bet he would consume half with a 10w40 oil change.
Caporegime
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How so?
there is no benifit using special oils as they get rebuilt end of every race
Amen to that, but I think those days are well and truly gone.
Once the petrol runs out things will probably get a lot simpler.
Are you being serious?
Of course there's benefits! Yes the oils will be replaced every race, but it's not the long term wear performance we're talking about here, in race engines. If they can run a thinner oil while still maintaining the protection required they'll get that bit more power out of the engine. That's just 1 of a wide range of reasons why an oil tailored to the race engine being used is a benefit.
Also, benefit. NOT benifit.
Why would OEM put in thick oil and lose out on Fuel economy benefits ??
Well to some people fuel economy isn't the most important reason for buying a car, so each to their own, they are hardly comparable to B&W TV.
But extra fuel economy without sacrificing something else is surely a win win situation. Free money basically!