Oil Change Question [Archive] - VWWatercooled Australia

TomC

20-05-2011, 09:37 PM

Thinking about going to stg 1 and beyond in my mk5 GTI. But I'm trying to decide what to do in terms of regular oil changing.

Up to this date I have got the car serviced to manufacturer specifications i.e. every 15,000km and minor/major as per logbook. Before everyone jumps on and says change it every 10,000km or less, here is my question:

My car is a fairly heavy oil user (about 1L per 1500km on rough calculations), which I suspect might be due to the way it was driven by the first user?!! So I'm topping up the oil every 3000km or so with fresh oil.

Now, if I'm adding new oil at this frequency does this lower the need to change the oil out of the car completely before the 15,000 VW recommendation? Or is that oil just added to the old oil in the sump and therefore become "dirty" as well? Looking for considered responses, rather than people's preferences if possible, because I know everyone has a slightly different personal opinion about changing their oil :P

R36FTW

21-05-2011, 07:40 PM

Damn that's a lot of oil, must have a pretty ****ty seal between the cylinder wall and rings (either that or your valve stem seals are shot). Personally I wouldn't bother modifying a car with an engine like that, but if you are going to despite its condition, there's 2 options IMO - just top it up as you need to and change it properly every 10-15K kms, or treat it like it's in good condition and change it more regularly (ie: 5-7.5K kms). Regular full changes would be better, but whether or not its worth it is your call.

TomC

22-05-2011, 12:03 AM

According to the manual and the dealer - when I questioned it last service - this engine (2.0TFSI) can use up to 1L/1000km. They did a quick scan but found nothing wrong. The car has been serviced by dealer like clockwork since new so I think calling the engine in poor condition might be a bit strong.

Spent a bit more time last night doing the calcs and I reckon it's closer to 1L/1750km. It's improved the longer I've had the car :)

Any other opinions on OP question?

R36FTW

22-05-2011, 03:42 AM

I wasn't having a go or anything and didn't mean it to sound like a strong statement, but Audi/VW engines have a bad reputation for excessive oil use, and 1L in ~2000km is pretty bad compared to say most Japanese engines. My Evo uses no oil (visible on dipstick anyway) in 5000km, even driven spiritedly. My mates GTR34 uses none either. No top ups in a full oil change interval with oil still at full line. I'm yet to see if my VR6 uses any, its still in the run in period.

The rings in your engine either don't seal properly (in which case you may be losing power too), the valve stem seals are leaking, or your turbo seals are leaking, have you checked the intake pipe for oil residue? Dealers tend to say "its fine" up to the point of failure depending on how dogy they are, but since those engines are known to use oil due to poor ring seal, I guess it might me 'normal'. Audi/VW I believe say up to 1L/1000 miles is ok,but to me that's ridiculous and indicative of a poor ring seal or other issue.

The_Hawk

22-05-2011, 06:02 AM

The handbook for the VR6 says up to 1L/100KM is normal so it's not just the dealers.

Transporter

22-05-2011, 02:45 PM

At the end of 70's and right till 90's, the engine that used more than 0.7L/100km was considered as worn out and in need of rebuild.

When the engine oils with the viscosities 5W30 and lower came to the market, many engines started to use more oil than normal and the car manufacturers simply announced that the oil consumption of 1-1.5L per 1000km was normal.

When checking for excessive oil consumption, remember to check the intake system and the intercooler for heavy oil deposit in them, caused by leaking/worn out turbocharger. It happens to the new cars with as low as 40,000km.

R36FTW

22-05-2011, 05:19 PM

Yes, but there are many engines that run high boost with 5W-30 or thereabouts and use none ie: 4G63, RB26DETT. As I said before Audi/VW engines have a reputation as oil burners. If you know why they are burning oil its up to you to say if its ok or normal, personally a late model engine with poor ring seal or leaky valve stem seals is not acceptable, and I would get rid of the vehicle, not modify it and by doing so increase its oil consumption (raise boost etc). I had an old nissan as my second vehicle which at the end of its 21 year life used 1L/1000km and when I pulled the engine down the valves were encrusted with soot from the oil combustion and the headers were full of it. The engine was gone, no-one said 1L/1000km was ok, not a mechanic, nor anyone with any vehicle experience. If its the rings on the Audi's that wont seat the run in procedure needs to be looked at - either too gentle or too hard. Beyond that the metals used for rings and cylinders may be the issue or QC in the factory, but they're hardly likely to admit fault with the design at this stage. Some guys have issues and some don't, but I've not read anything conclusive as to exactly why it happens.

I asked the OP in my previous post if he'd checked the intake for oil indicating turbo seal failure, but he has not replied.

Transporter

22-05-2011, 06:47 PM

Hm, Japanese cars usually don't specify only 5W30 but allow much heavier grades to be used, so it could also mean that they use heavier oil right from the first oil change. Keep in mind that 5W30 oil is usually at least semi-synthetic (more expensive) and many workshop would use the cheapest oil they can get away with and still be within manufacturers specs.

I have 4 VW in family and none of them use oil. All serviced by me (every 7,500km or more often), never been to the dealer for the oil change. I agree 15,000km or 12 months is way too long between oil changes. IMO, oil should be drained as soon as the car comes of the boat, who knows how long the engine spent idling and how many short trips the car had when it left the factory.

R36FTW

22-05-2011, 08:09 PM

I wouldn't say 'much heavier' grades can be used in japanese cars, my Evo needs 10W-30 for our temp conditions according to the manual, but SAE 40 is ok too, no thicker according to the manual. Mobil1 0W-40 is factory fill for GTR's. That oil often shears to a heavy SAE30 pretty quickly. Thin oils are usually specified these days for 'eco friendliness' not engine life extension (same reason they're reducing the amount of additives and detergents in oils), SAE 30 is as thin as I'd go in Australia. The japanese build engines tighter than anyone and they are around the SAE30 mark. Something like German Castrol would be ideal but I doubt the aussie dealers use it. I'd be pissed if VW used anything less than full synthetic in my car though, it has to meet 504 spec so there are a few decent choices available, but if they dont I'll find somewhere that does and use them for my factory servicing instead. I'd do it myself but I'd then not have the service logbook which most people insist on when buying second hand.

Plenty of people have oil burning issues with certain audi/VW engines. Not so much with any other brand from what I've noticed. They even mention it in audi/vw car reviews sometimes as a 'trait' of the vehicles. It's just poor form these days IMO, rings should seal, end of story. If someone's ok with them not sealing that's up to them, I think its unacceptable.

TomC

22-05-2011, 10:03 PM

In reply to the question, I had the whole intake off a couple of months ago and no oil residue present unfortunately. Don't get me wrong, I'd be more happy if the car didn't use oil like it does, but it has been flawless since new for both the first owner and now me so I don't have any major concerns.

I don't have enough knowledge or desire to get into the whole oil use in different types of engines debate (although I did have an SR20 before buying the Golf so I'm not foreign to Jap engines).
Just looking for an answer to the original question.

here is my question:
Now, if I'm adding new oil at this frequency does this lower the need to change the oil out of the car completely before the 15,000 VW recommendation? Or is that oil just added to the old oil in the sump and therefore become "dirty" as well?
Cheers

Transporter

24-05-2011, 09:01 AM

Plenty of people have oil burning issues with certain audi/VW engines. Not so much with any other brand from what I've noticed. They even mention it in audi/vw car reviews sometimes as a 'trait' of the vehicles. It's just poor form these days IMO, rings should seal, end of story. If someone's ok with them not sealing that's up to them, I think its unacceptable.

I can tell you that plenty of people don't check their engines oil level and Subaru engines could have an appetite for the oil too. :)

I see plenty Jap engines that drain 1/2 of the original oil fill and quite a few of them are badly sludged at much less than 100,000km. It all comes to the maintenance, how good it is and it starts with the owner of the car.

This is 2006 Toyota Yaris and the oils that you can use in the engine. The rest of Toyota models are very similar including the latest ones. Only hybrids call for 0W20.

http://www.vwwatercooled.com.au/forums/images/imported/2011/05/5752288789_a433768554_b-1.jpg (http://www.flickr.com/photos/60080395@N04/5752288789/)

You could use the 20W50 oils in these VVTI engines in every part of Australia. That's right they're suitable up to -7 deg. C. :dunno:

brad

25-05-2011, 08:43 AM

Transporter

25-05-2011, 09:04 AM

To the OP:
If you are adding 0.5L/1000km then that = 7.5L/15,000. That's almost 2 oil changes, so your additive pack is certainly being kept at maximum spec. The oil filter has plenty of capacity to hold contaminants & gets more efficient the closer you get to 15,000km.

I guess it depends on how hard you drive it. I have stage 1 but don't consider that I drive my car very hard & usually stick to 15,000km changes. My engine uses no oil & I had the oil tested at the last change & it was like new.

If it was me, I'd stick with 15,000km changes & keep driving it as you do in the hope it will seal up a bit more.

also, it spends more time on the bypass (bypass valve opens and will stay open for longer time due to the restriction to flow) when you get no filtration at all. So you get unfiltered oil circulating through much longer, especially in cold. :(

I also disagree that the filter is big enough. But hey, it's only my opinion, but not the above, which you can bank on. :)

brad

25-05-2011, 09:14 AM

Bypass only comes into play if the oil pressure required to get through the filter is greater than the spring pressure of the bypass. yes/no?

And your saying that the OEM filter when fitted to an engine that has regular 15,000km changes is incapable of getting through the 15,000km without excessive plugging? This is the same filter that in Europe/UK is subject to change periods of up to 30,000km/2 years?

R36FTW

26-05-2011, 09:40 PM

Yes, bypass opens at a certain oil pressure which is driven high by increasing resistance in the filter element. Oil pressure at cold start can be 4-5bar (58-72.5psi) which is way over what most bypass valves open at. Oil pressure at high RPM can be 70+psi depending on the engine and oil pump, so at high revs its not uncommon for the bypass to be wide open too. Most people think their oil filter is filtering all the time, but its not the case at all.

Transporter

26-05-2011, 10:12 PM

Yes, you‘re correct there, when more pressure is needed for the oil to get through the filtrating element, the bypass valve in the filter will open. When the filter is clean there is a less restriction to flow, the bypass valve may stay closed, but as the filter is getting more clogged up the bypass valve will start to open to allow unfiltered oil to lubricate the moving parts, since the dirty oil is better than no oil.

I don’t know what is the micron rating of the OEM filter on Skoda and VW engines, but I could speculate here a bit; since it is a long life filter (as brad say 30,000km/2years) which is not really big in size and has a back pressure set to 2.5 bar, the micron rating could be around 50 or 60 microns. Which is not good for short trips and oil changes every 15,000km or 1 year or even longer.

Anyhow regardless of the age of the filter and the oil, the bypass valve in the filter also opens at high engine RPM’s to keep up with the lubricating demand of the fast moving rotating parts. With the dirty oil and filter, it opens sooner and for longer.

A bit of reading for those interested Oil Filter Advice (http://www.machinerylubrication.com/Read/681/oil-filter) good info if you do extended oil changes.

R36FTW

26-05-2011, 10:31 PM

Yeah would like to know its micron rating. Most paper element filters are something like 98% at 30 microns and 85% @ 20 microns, and most engine wear is caused by particles 10-30microns, which when you think about the particle size in relation to the bearing/piston to cylinder clearances is quite large.

There is no way I'd run a filter for 15000kms if I could help it. The filter doesn't get more efficient as it approaches 15000kms, the gunk may catch more small particles but the bypass will be open for longer and more often so unfiltered oil will be circulating throughout the engine more often. This is hugely detrimental and will rapidly accelerate engine wear.