Synthetic Oil????

Pottler

Had an interesting conversation today with a man who I regard(and pretty much everyone else regards)as being an expert mechanic and performance tuning/engine modding guru who shall remain nameless.
He was showing me an absolutely smashing car(performance Audi) that he bought for buttons and rebuilt the mashed engine and now had for sale.
Anyhoo, the salient point was that he blamed the previous engine damage on the use of 5w30 synthetic oil and advised me to use 10w40 top quality mineral oil instead, as synthetic brews had the damaging effect of "varnishing" the engine components to the point of self-destruction. He said that mechanics (main dealer) who deal with Audi/Vw daily never use synthetics in their own cars but opt for 10w40 instead. As a previous full time user of 5w30 synthetics in the ten vehicles I run, I was a bit preturbed. His view basically was "synthetic can be trouble, use 10w40 mineral instead, it's better". Any comments on this? BTW, this is a seriously bright lad who told me this, bear that in mind please.:) I'm confused!

Voodoomelon

What model and year is the Audi?

Pottler

It's an 02 ish, but I'm no way mentioning the model as its a prominent car and I do not want to involve said chap in any way - it was a private conversation but I'm just wondering if what he said was just blowing steam or was valid? I spend a bomb on "good" oil, all my yokes get 5w30 syn- as recommended. His opinion was just very counterintuitive.

Neilw

What engine is in the audi?

10w40 mineral oil for a 2002 reg performance Audi? Can't see any forced induction Audi from 2002 enjoying that experience longterm, dunno about the V8s or other large capacity NASP models.

jopas83

Mineral oil for old cars(12-15yrs) with lots of miles.
Synthethic for newer cars.

Pottler

RoverJames wrote: »

10w40 mineral oil for a 2002 reg performance Audi? Can't see any forced induction Audi from 2002 enjoying that experience longterm, dunno about the V8s or other large capacity NASP models.

Nope, view expressed was, 10w40 top quality mineral in ALL engines instead. I only posted this as this guy knows his onions and I'm running 5w30 fully syn in almost everything. He reckoned I was doing wrong, reckoned that when an engine flush was conducted on a fully syn brewed motor, the red slush purged was unreal - varnishing was the term used.

Pottler

jopas83 wrote: »

Mineral oil for old cars(12-15yrs) with lots of miles.
Synthethic for newer cars.

Yes, I know that. Presuming you are a mechanical know-not-much, like me, that is the perceived wisdom. His view was, syn bad, mineral good. He knows a damn sight more than me(and presumably, you), so who's right?? I also see first hand how many complete engines are replaced by the big manufacturers under warranty, so maybe he is onto somthing?

Matt Simis

Granted he may have had a bad experience in the past... but this really sounds kinda absurd.

For one most "synthetics" are actually semi-synths due to some BS technicality, so all these people with an anti-synthetic agenda (usually really old school types who talk about "leaks" a lot) are basing their argument on a fundemental misunderstanding of the product. True synthetics (Mobil 1 is one) are excellent. I use Synthetics in my 18, 16 and 14year old cars and always have.

Performance MPower engines and virtually all BMW engines in the last 15years are recommended by BMW to use Synthetics. Considering they could resell cheaper mineral oil at a higher profit but choose not to, I think there is a good reason for this. Audi are of course the same.

That reason of course is the "black death" that plagues mineral oils subjected to high thermal loads and wide temp extremes.

One key problem I have with this conversation is the assertation that varnish is somehow a problem. Um.. how exactly? Its a colour on the metal. What kills engines is sludge, which is caused by Oil breakdown which is what happens if you foolishly put mineral oil in a performance motor:
http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=1536298


PS: Images of varnish.. note that its clearly a microscopic surface coating, here is me changing the VANOS unit on a 530i, note no sludge:


And me fixing loose cam bolts on an 850CSi, varnish on a near 20year old engine, no sludge:



When I take the sump off my M60 V8 engined 540i (Ill take photos!) I expect Ill see some varnish too, despite it likely having Semi-synths in it all the time. Varnish is harmless, sludge and in BMWs case, f-ing loose bolts are the killers.

Did he mention what he reckons the effects of this varnishing is? I imagine the negatives are a lot less than the likes of sludge and if you run a turbo car (particularly a 1.8T Audi) on 10w40 mineral oil you'll be getting that which leads to oil starvation

Pottler

RoverJames wrote: »

Did he mention what he reckons the effects of this varnishing is? I imagine the negatives are a lot less than the likes of sludge and if you run a turbo car (particularly a 1.8T Audi) on 10w40 mineral oil you'll be getting that which leads to oil starvation

Blocked and failed oil pumps, blocked oil galleries on cams, seized and worn crank bearings. This buck goes deeper into motors than I would ever dare and makes a fine living rebuilding high end cars with dead engines bought rock bottom and revitalised.

alexlyons

you've got a few responses with people expressing their view but you seem to reiterate what you've already said and indicate that others could be wrong, but still ask who's right. Nobody is going to give their opinion and say "but i'm wrong".

the only way your going to get a response that I reckon you'll accept, is by talking to another mechanic or two.
the next best thing is to take the general consensus on here and go with that, but I'd suggest not asking people and then all but saying "no your wrong because he said this".

jopas83

Pottler
Don't listen this guy anymore.

Pottler

Pottler wrote: »

Blocked and failed oil pumps, blocked oil galleries on cams, seized and worn crank bearings. This buck goes deeper into motors than I would ever dare and makes a fine living rebuilding high end cars with dead engines bought rock bottom and revitalised.

I'd class those problems as being more likely due to missed services or folks not getting frequent enough oil changes, as Matt's pics show varnish on an engine is more or less a cosmetically noticeable feature, it doesn't insulate parts against lubrication or anything

alexlyons

alexlyons wrote: »

...............

the only way your going to get a response that I reckon you'll accept, is by talking to another mechanic or two.
the next best thing is to take the general consensus on here and go with that, but I'd suggest not asking people and then all but saying "no your wrong because he said this".

Indeed, I was tempted to say he might well be a talented mechanic but he seems to be a bit thick :pac:

Pottler

jopas83 wrote: »

Pottler
Don't listen this guy anymore.

Hmm, I wouldn't, if so many others didn't trust him to work on their cars. Also, if he didn't drive cars that make everyone else drool, I'd pay him no mind.

Pottler

RoverJames wrote: »

Indeed, I was tempted to say he might well be a talented mechanic but he seems to be a bit thick :pac:

Probably regarded as a genius by most though. You have no idea how wide of the mark you are James.:) Anyway, just thought it was the most controversial motoring "gossip" I'd come across. Might drop it now, but I know whos advice I will be following:pac:

Pottler

Pottler wrote: »

Probably regarded as a genius by most though. You have no idea how wide of the mark you are James.:) Anyway, just thought it was the most controversial motoring "gossip" I'd come across. Might drop it now, but I know whos advice I will be following:pac:

.... as mentioned, why bother asking if you intend to repeatedly defend the chaps views rather than looking at the posts in the thread here and thinking about it yourself ?

What he recommends is contrary to the research and practise of the last two decades at least and there are no shortage of varnished up engines running perfectly with no blocked pick ups. Twould take some amount of varnish to block an oil pump too

To summarise, what oil are you going to put into your car at next service?

Pottler

10w40 mineral, -you put in whatever you like:)

Pottler

Pottler wrote: »

......... As a previous full time user of 5w30 synthetics in the ten vehicles I run........

http://www.boards.ie/vbulletin/showthread.php?p=77164565

You run them on 5w30 synthetic?

Voodoomelon

I cannot believe that non-synthetics should be used in modern engines. Notably BMW engines as mentioned; the use of non synthetics completely counters the manufacturers recommendations for the last 15 years.

Having said that, there was one reported case on a BMW M62 V8 on the american forums where a user did very regular oil changes with fully synthetic for many, many years and on lifting his valve covers, the engine was destroyed with sludge. He could not believe it and was absolutely disgusted. Not sure he ever got to the bottom of it. (wasn't oil pump related)

conzy

I have heard that using 10w40 instead of 5w30 can reduce oil consumption on engines that are fond of oil. But surely it doesn't provide the same performance at high rpm / Turbo charged situations so I don't see why it would be recommended for a modern high performance engine.

conzymaher

conzymaher wrote: »

I have heard that using 10w40 instead of 5w30 can reduce oil consumption on engines that are fond of oil. But surely it doesn't provide the same performance at high rpm / Turbo charged situations so I don't see why it would be recommended for a modern high performance engine.

... it doesn't provide the same protection for cold starts or when the engine is at operating temp either

Pottler

RoverJames wrote: »

http://www.boards.ie/vbulletin/showthread.php?p=77164565

You run them on 5w30 synthetic?

I knew You'd put that up and actually, yes I do, for the last year or two:) I also run a good few other, somwhat newer yokes:) Personally I drive relics, always have, always will, it's ingrained. I don't expect anyone who works for me to do the same though. What I do or don't drive is irrelevant. Jasus, usual internet warrior battle. Point is, a fair few main dealer mechanics eschew synthetic oil in favor of 10w40 mineral oil in their own cars. Must be a good reason, I reckon. BTW, the dispatch is my all time favorite vehicle and financially I can drive pretty much whatever I like. Maybe I'm odd?

Pottler

Pottler wrote: »

I knew You'd put that up and actually..........

You know a lot for a new poster

Why were you putting 5w30 synthetic into them yokes?

Pottler

RoverJames wrote: »

You know a lot for a new poster

Why were you putting 5w30 synthetic into them yokes?

Nothing new about me Jamesey, apart from the username.:) Thought 5w30 was the best, and sure only the best is good enough for my wagons:) May review my definition of "best":)Postcount should read '+00 ish, but there ya go.

RandomAccess

At a guess it sounds like it was a 1.8T, every dog on the internet has heard at some point that these engines are sensitive to the kind of oil used and that if you don't use synthetic with correct oil change intervals then you are in for a world of trouble.

Now either you heard him wrong or he had a brain fart when he was telling you that and it got swapped around.

Obviously this is all assumption and internet-fact, so its just my 2cents

Bruthal

Pottler wrote: »

and sure only the best is good enough for my wagons:) .

Best not let the mrs hear you sayin that, she might take you up wrong.

Nissan doctor

Pottler wrote: »

Nothing new about me Jamesey, apart from the username.:) Thought 5w30 was the best, and sure only the best is good enough for my wagons:) May review my definition of "best":)Postcount should read '+00 ish, but there ya go.

So we should all stop wasting our time on a spam thread written by a previously banned troll?


No top mechanic or major engine tuner told you to use mineral oil in modern performance turbocharged engines!

Pottler

Nissan doctor wrote: »

So we should all stop wasting our time on a spam thread written by a previously banned troll?


No top mechanic or major engine tuner told you to use mineral oil in modern performance turbocharged engines!

Nope, wasn't banned, just left a fair while back. The advice he gave me was just an off the cuff remark while we were discussing a car he had just finished rebuilding and had for sale. He has another coming with the same problem - bottom end destroyed due to oil starvation. I'm not trolling Nissan, I run fully syn in all the CRD engines we have but he said to switch to Castrol 10w40 semi and ignore the extended drain interval, go to 6000km intervals instead of 20000km. Apparently thats what an awful lot of main dealer mechanics are doing with their own private cars. Seems from the responces that pretty much nobody agrees with what was said, which is fine(and actually good, cos my own yokes are on fully syn!) Had a sleep on it and maybe what ye are saying is right - anti syn could just be a personal crusade he's on, who knows. One of our vans is on a 40000km service interval, considering it cost me €36k, I have no huge desire to see it cack itself! Hence I asked the question.:)

Whatever about 20000km intervals, 40000km is way too long imo, if I was you I'd halve that but still use the recommended oil rather than a 10w40

gyppo

Pottler wrote: »

he said to switch to Castrol 10w40 semi and ignore the extended drain interval, go to 6000km intervals instead of 20000km. Apparently thats what an awful lot of main dealer mechanics are doing with their own private cars. Seems from the responces that pretty much nobody agrees with what was said, which is fine(and actually good, cos my own yokes are on fully syn!) Had a sleep on it and maybe what ye are saying is right - anti syn could just be a personal crusade he's on, who knows. One of our vans is on a 40000km service interval, considering it cost me €36k, I have no huge desire to see it cack itself! Hence I asked the question.:)

I can't say I agree with lubricating a modern engine with 10w40, but I do see the merit in shorter oil intervals. I feel that many recommended service intervals are very long, except on cars that are racking up the miles quickly.

deandean

OP, there are two issues here:

(1) Viscosity. 5W30 -v- 10W40. The former is 'thinner'. An engine is designed with a particular oil viscosity in mind. I would not put 10W40 oil into an engine designed for 5W30 unless there's a very specific reason (age, track use, etc).

(2) Mineral -v- synthetic. TBH it prob doesn't make a huge difference in a normally aspirated engine if the oil is being changed very regularly, e.g. every 3K miles or so. But you wanna have the fully synth for the stupidly-long service intervals you see in modern engines. Also - have you ever had a car with an oil pressure gauge? You'll see that at high oil temperatures, oil pressure stays up with synth oil whereas it drops off with mineral oil. Better oil pressure obviously means better lube supply to the engine bearings.

If I had a performance Audi I'd use whatever oil Audi recommends!

TestTransmission

Pottler wrote: »

Nothing new about me Jamesey, apart from the username.:) Thought 5w30 was the best, and sure only the best is good enough for my wagons:) May review my definition of "best":)Postcount should read '+00 ish, but there ya go.

Nissan doctor wrote: »

So we should all stop wasting our time on a spam thread written by a previously banned troll?


No top mechanic or major engine tuner told you to use mineral oil in modern performance turbocharged engines!

Sounds like a plan