Bmw 5 series petrol TURBO - Engine flush - sammy1

My independant garage has suggested an engine flush before the new oil change.

My question is will this help clean the oil pipes which lubricate the turbo or is this merely transfering gunge back into the sump and oil pump but will obviously leave when the flush is drained. How much flush remains to dilute the new oil?

What are your thoughts please the car is only 15k miles.

Bmw 5 series petrol TURBO - Engine flush - RobJP

You have gone to an independent when your car is still under warranty.

Basically, by doing so, in the event of a warranty claim, it will be up to you to PROVE that all parts and workmanship have been to OEM standard - so insisting on getting the independent garage on supplying you with their invoice for the oil filter and oil used, by providing a completed checklist (and it had better match everything that the 'official' BMW checklist covers), and you've then got to keep all that paperwork as evidence of it all being done.

Can't provide that proof - BMW will be entirely entitled to tell you to get stuffed, as long as any failure is related to items that require maintenance.

In addition, you won't get the benefit of any TSBs that may be issued by BMW (these are non-safety critical equivalent of recalls, but they aren't recalls because they aren't safety-critical), or any updates.

All for the sake of probably saving £50 or so.

Edited by Avant on 20/04/2017 at 17:43

Bmw 5 series petrol TURBO - Engine flush - Ian D
Agree with Rob, plus your chances of any just out of warranty goodwill contributions will be reduced
Bmw 5 series petrol TURBO - Engine flush - jc2

Most dealers/garages will try to sell you oil and fuel treatments at great expense telling you that they are recommended by the manufacturer-they're not.Manufacturers tell you only to put recommended oil into the engine-nothing else. Anyway most flushing oil has a large percentage of paraffin.

Edited by jc2 on 19/04/2017 at 18:40

Bmw 5 series petrol TURBO - Engine flush - sammy1

My 5series is 5 years plus genuine low miles and well out of warranty. All I am asking is a genuine question on the pros and cons of engine flushing from experianced engineers on the forum. The cost of the flush is about £25inc VAT. On the face of it flushing seems to be a good idea. I am a mature male who souces my cars privately from like minded individuals and begrudes giving money to dealerships who happen to have cars for sale at a ridiculous mark ups and charge serious money for servicing. I do not like the BMW dealership experiance, selling or service, I do not trust them

Bmw 5 series petrol TURBO - Engine flush - bazza

If you've changed the oil and filter regularly and driven the car so that it gets to operating temperature routinely, I would personally not bother. However if it has stood for months or years and just gets the odd drive down the road, I would be tempted. I know nothing about this engine, does it have a reputation for sludging?

Bmw 5 series petrol TURBO - Engine flush - Ian D
Thanks for clarifying age of car, wow that is low mileage. My experience is that regular oil changes (draining via the sump plug, not sucking oil out) using correct oil + quality filter is all you need, avoid the flushing. Oil and filter every year or 6k to 10k miles (6k if short journeys) seems sensible to me.
Bmw 5 series petrol TURBO - Engine flush - SLO76
Agree totally with your anti-dealer thinking Sammy. If you have the knowhow to get a good car and are willing to take a bit of a gamble then go for it, 99% of punter don't though and would be ill advised to follow you. I wouldn't bother with a flush though. Assuming your car has seen fresh oil (correct grade) every year then it should be like new in there.

I would however be wary of having a complex car like this serviced by an independent. They simply don't have the expertise and equipment to properly maintain something like this despite what they'll be telling you. Nine times out of ten small garages like this don't use the correct grade of oil as they bulk buy oil with a view that 'it'll do' which isn't wise on modern motors which are highly oil specific. Use the wrong stuff and you'll encounter plenty of woe later on, particularly timing chains and turbochargers on BM engines. Spend the extra and maintain it properly, it'll repay you with reliability and a higher resale price. It really is a false economy.

I made the same mistake once. Bought a nearly new E46 2.0 Coupe and after a couple of years servicing it at the main dealer I switched to a local so-called BMW specialist. Within months it developed a rattling timing chain at 47,000 miles thanks to said specialist using the incorrect grade of oil. He refused to accept any wrongdoing and rather than face a legal battle i offloaded it through the trade quickly to a dealer who was daft enough not to start it. I'd never sell a duff car retail but as far as other traders are concerned it's buyer beware.

Further point on dealer servicing. You can negotiate on their prices. Get a quote from a BM specialist within range of you then ask the main dealer to match it. They usually will discount to get close and for all the difference there is you'll more than make it back come resale.

Edited by SLO76 on 19/04/2017 at 22:02

Bmw 5 series petrol TURBO - Engine flush - RobJP

Thanks for clarifying the age of the vehicle - that changes what my reply would have been.

It all depends on how often in the past the oil has been changed. It's quite possible that it's had no (or 1) changes in the past, in which case I'd be tempted to get a flush done with the oil change now, and then to get another change done in a couple of months.

If, on the other hand, it's had annual oil changes, then just get it changed, and keep on doing that every year.

As for BMW service pricing, a couple of things to note.

Service prices can vary - some dealerships can be cheaper than others, and you can play them off against each other.

Also, once the cars get a bit older, BMW servies prices get cheaper - check on here : www.bmw-service.co.uk/value_service/5_series you might find the standard prices not as extortionate as you might have feared, and even the 'fixed prices' can be up for negotiation.

If you don't ask, you don't get ...

Bmw 5 series petrol TURBO - Engine flush - brum

The best engine flush technique is simply to change oil more regularly. Change at 5k instead of 10k and you dont need to change the filter at that mid interval so its a 10 minute job. Top quality (correct spec) oil has all the additives needed to clean/keep clean your engine on an ongoing basis with no risk of compromised lubrication.

Bmw 5 series petrol TURBO - Engine flush - John F

The best engine flush technique is simply to change oil more regularly...

If the OP and any previous owners have followed HJ's absurd anachronistic advice for annual oil changes (causing needless expense for those who often can least afford it), it will have had four already at roughly 3000m intervals. Even it has had only one or two, I agree that no flushing is necessary. Modern oils, tight fitting pistons and valve stems (Minis and certain Audis excepted) plus complete combustion result in virtually no sludge formation. Gone are the days when one could remove gunge with a spoon from the OHV cover of a neglected engine.

Incidentally, OP, I believe there are very few experienced engineers (Mech Eng) posting on this site but there are a large number of mechanics, some of whom (the older ones I guess) have dated dogmatic opinions concerning oil changes!

Bmw 5 series petrol TURBO - Engine flush - SLO76
Scrimping on oil changes on a complex and valuable car like this is a complete false economy John. As a salesman the first thing I'd do after physically appraising a car like this would be to verify the thing has a full service history which had been carried out by someone who knew what they were doing. If it didn't then the valuation would be hugely revised down, on modern prestige and performance metal it can make thousands of pounds of difference and will wipe out any savings made.

Further to this, BMW's are notorious for timing chain and turbocharger issues and these are often due to a lack of regular oil changes or the use of the incorrect grade of oil by garages/owners who've no clue.

With low mileage use, where the engine doesn't often reach full operating temperature and thus the moisture in the oil doesn't full burn off this is even more important not less so. Pop the filler cap on a low mileage city car or supermini that's seen local use only and you'll often find a congealed milky build up that's often mistaken for head gasket failure. This reduces the oils ability to protect the engine and can block oil pathways to vital components such as turbochargers and timing chains. This is why so many Micra's, Corsa's and Almera's suffer from failed and stretched chains.
Bmw 5 series petrol TURBO - Engine flush - RobJP

The best engine flush technique is simply to change oil more regularly...

If the OP and any previous owners have followed HJ's absurd anachronistic advice for annual oil changes (causing needless expense for those who often can least afford it), it will have had four already at roughly 3000m intervals. Even it has had only one or two, I agree that no flushing is necessary. Modern oils, tight fitting pistons and valve stems (Minis and certain Audis excepted) plus complete combustion result in virtually no sludge formation. Gone are the days when one could remove gunge with a spoon from the OHV cover of a neglected engine.

Incidentally, OP, I believe there are very few experienced engineers (Mech Eng) posting on this site but there are a large number of mechanics, some of whom (the older ones I guess) have dated dogmatic opinions concerning oil changes!

Before taking any advice from John F regarding oil changes, bear in mind that he has absolutely no qualifications or expertise, apart from his individual experience of his 'highly engineered' (his own words, from way back) TR7, which he changes the oil in every few years. Or if he does have any qualifications, he's declined to tell us them, in spite of being asked (usually when asked he vanishes for a few weeks, conveniently abandoning the thread).

The rest of us have various levels of experience and expertise. We have race engine builders, mechanics (professional ones), people who sell cars for a living (and won't touch things with occasional oil changes, as they come back to bite them too often), myself (16 years working in oil development and testing, with a BSc and MSc to back it up), HJ (the man himself), along with a host of others.

We nearly all reckon that John F is talking out of his rectum. He reckons we're in some grand conspiracy to cost motorists more money.

Make of it what you will.

Edited by RobJP on 24/04/2017 at 11:42

Bmw 5 series petrol TURBO - Engine flush - madf

15,000miles in 5 years is seriously low mileage.

IF any of it is short journeys - under 5 miles in winter - teh engine will never have reached operating temperature and any condensation in the engine will be present in the oil. As will be dilute amounts of excess diesel.

Flushing will make no difference to those. Regualr oil changes will. I treat John F as a classic car enthuisiast whose technical knowledge stopped in teh late 1970s when ihis Triumph was designed... (It was pants then as well). Take his advice as much as you would trust a politician.

Bmw 5 series petrol TURBO - Engine flush - John F

Before taking any advice from John F regarding oil changes, bear in mind that he has absolutely no qualifications or expertise, apart from his individual experience of his 'highly engineered' (his own words, from way back) TR7, which he changes the oil in every few years. Or if he does have any qualifications, he's declined to tell us them, in spite of being asked (usually when asked he vanishes for a few weeks, conveniently abandoning the thread).

You clearly missed my response to your criticism in an earlier thread, RobJP.

Thu 1 Dec 2016 16:17

Any - HJ's Saturday Telegraph annual oil change advice - John F

Hi, I'm back, thanks to RobJP's invitation on another thread. I'd forgotten about this one. I've enjoyed wideranging opinions about Saabs which I had not seen and salute the academic achievements and experience of my detractors.

My qualifications for venturing an opinion about chemical and physical matters are merely decent grades at chemistry and physics 'A' level by the age of 17 (in the 1960s when 'A' levels were arguably more difficult than today's) and a subsequent lifelong interest in engines of one sort or another. We were told that the biochemistry component of our medical course was the equivalent of a BSc but by then I was specialising in the study of a live machine far more complex than mere internal combustion engines, fascinating though they are.

I am of course aware that the more frequently one changes oil, and the better its quality, the longer the engine will last. All I am saying is that annual oil changes are unnecessary for the average low mileage driver who does not need the engine to last for 250,000m.

By the bye, my 36yr old 70,000m TR7 passed its MoT yesterday - no advisories, engine humming sweetly, has never required any attention apart from its water pump and trimming the ends of the original HT leads. Last oil change 2013.

The rest of us have various levels of experience and expertise. We have race engine builders, mechanics (professional ones), people who sell cars for a living (and won't touch things with occasional oil changes, as they come back to bite them too often), myself (16 years working in oil development and testing, with a BSc and MSc to back it up), HJ (the man himself), along with a host of others........

.......with whom I am perfectly entitled to disagree without incurring rancour and offence..............

We nearly all reckon that John F is talking out of his rectum. He reckons we're in some grand conspiracy to cost motorists more money.

Yep. It's called the motor trade. And in the course of my life I have seen the distress it can cause people, especially women of modest means, both young and old, with no mechanical knowledge and who struggle to keep their old low mileage cars on the road, by advising expensive unnecessary work without giving a thought to a cost benefit analysis.

Oh, and in addition to the above, I forgot to mention that I was briefly a MENSA member. All of which helps me to distinguish between the sense and nonsense that is disseminated so widely on the internet.

Bmw 5 series petrol TURBO - Engine flush - Terry W

Not an engineer but an accountant who used to do his own car maintenance.

The cost of an oil change is around £50. The cost of a cylinder head failure (valves etc) will be £500 - 1000 or more. Full engine failure or rebuild (oversize pistons, scored bores etc etc) is £'000s.

My petrol Octavia takes aroud 6-10 miles to get up to full operating temperature (oil 90C +) Short journies mean that rubbish builds up in the engine oil, cat, etc.

Spending an extra £50 every (say) 2 years to avoid most of these problems, the hassle of failing transport and a negative impact on trade in value is a no brainer.

The only exception may be the bangernomics end of the market - where one buys on the basis of a valid MOT, and condition,, spend money only when essential,, and be prepared to junk it if it needs any real money spent.

Bmw 5 series petrol TURBO - Engine flush - RobJP

There we have it then - John F's qualifications of A level in Chemistry and Physics, which 'he was told' are equivalent to a far higher level of qualification these days. I'm surprised he wasn't involved in the Space Shuttle missions, being so eminently qualified. I must remember that in the future - hell, why get a modern qualified surgeon who has studied for years, when someone who took their A level in biology in the 60s is undoubtedly better qualified to do the job.

Along with his membership of MENSA, and not forgetting his ownership of the dizzy heights of BL engineering excellence, in the form of a TR7.

Much as I hate to inform you, John, but having membership of MENSA doesn't mean much. It certainly doesn't imply any common sense. I suspect it's a bit of a security blanket for those who brag about it; 'The last refuge of a scoundrel', as Samuel Johnson would say. I know a couple of people who I would describe as 'genius' intellect, and they seem to struggle with basic concepts, getting bogged down in detail - not able to see the wood for the trees, so to speak.

Personally, I'll take my qualifications and expertise from the 80s / 90s, along with the vast experience of others, as opposed to the tinfoil-hattedness of John's genius and his motor trade conspiracy theories.

Bmw 5 series petrol TURBO - Engine flush - FP

RJP seems very keen to put John F in his place - not for the first time.

I'm sorry, but I find it all very tiresome. It seems to come down to "I'm better qualified than you - yah boo sucks". It's far too personal for my taste and is so over-blown as to sound ridiculous. Stuff like "I'm surprised he wasn't involved in the Space Shuttle Missions", though intended to be sarcastic, is just silly. And equating a past A level in biology with the training of a modern surgeon is ludicrous - a huge exaggeration of what John F meant.

The quotation from Dr Johnson seems to be intended as a learned comment, but is irrelevant; Johnson was speaking about patriotism.

John F has his views. Others may regard them as extreme, odd, or whatever. That doesn't mean someone else who happens to disagree is entitled to be offensive about him. I notice John F's tone on this forum is consistently calm and pleasant, unlike that of some of his detractors.

Bmw 5 series petrol TURBO - Engine flush - John F

RJP seems very keen to put John F in his place - not for the first time.

John F has his views. Others may regard them as extreme, odd, or whatever. That doesn't mean someone else who happens to disagree is entitled to be offensive about him. I notice John F's tone on this forum is consistently calm and pleasant, unlike that of some of his detractors.

Thanks for your kind and reasonable words, FP. I have no idea why RJP is so excercised by my views, and apparently also by my abnormality confirmed over thirty years ago which affects over a million of the UK population. Having acceded to his request for personal information concerning my qualifications for expressing an opinion here, he then infers that I was bragging! Ho hum.

Bmw 5 series petrol TURBO - Engine flush - glidermania

Oh please. Stop giving out misleading consumer advice.

It is fully legal to have a car service while under warranty at a non franchise dealer.

The only 'proof' that is needed is \ are sales invoice \ receipt from a VAT registered garage showing the components used are OEM quality and not generic, sourced from the likes of Eurocar Parts ie Castrol Oil, Parts numbers for items that BWM use ie oil filter etc.

This is hardly onerous proof when using an indie or other reputable garage and in fact, the onus of proof is on the franchise dealer to show suitable service items havent been used when attempting to turn down a warranty claim.

That said, for best selling price and dealer goodwill, Id recommend maintaining full dealer service records for the life of the car. BMW dealers normally apply a service discount of around 20% for cars 4 years and over to combat the indie trade.

Bmw 5 series petrol TURBO - Engine flush - Metropolis.

Engine flushes are another of those 'two schools of thought' topics. I'm of the opinion that they are too severe, and will end up moving alot of crud into tight oil channels and other places it should'nt be. Does it have any symptoms that are making you concerned? I'd suggest as others have, change the oil regularly, say 6k. Fully synthetic, good investment if you're intent on keeping the car a long while. Make sure the oil is warm when you change it each time. Just double checked your question, with regards the turbo the best thing to keep it healthy is to run the engine at idle for a short while (nothing excessive, idling can cause issues in itself) in order for the turbo to stop spinning and cool down whilst still lubricated. Turn off the engine too soon after a run is a sure way to kill it! I am not an expert in any way. Just a shade tree mechanic going on experience and tips picked up over the years.

Bmw 5 series petrol TURBO - Engine flush - Avant

Nothing really surprises me any more, but I do wonder how some of you - presumably busy people like me - find the time to return every few months to this same topic - often, as here, not the one that the OP was asking about.

You'll just have to agree to disagree. Just as no two human beings are the same, so no two people will use their cars in exactly the same way. So oil changes may not be appropriate at the same time for everybody.

Manufacturers of course have to generalise in their recommendations: some have a different regime for high and low mileage motorists. Volvo's common-sense approach, which has the great advantage of being simple, is a year or 18,000 miles, whichever comes first. I'm going with that.

In terms of Sammy1's original question about flushing, I'm no expert, but the advice early on in the thread that it shouldn't normally be necessary but that if the car's low mileage is (or may possibly be if not known) due to lots of short trips, it could be beneficial.

 

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