About to top up your oil? STOP!! Read this first.

ScottyP45

ScottyP45

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Use only FULLY synthetic oil and never EVER top it up with any other kind. - it is said by many oil experts that mixing of synthetic oil with any amount - even a trace - of mineral oil causes the synthetic oil to break down and form black sludge - and vice-versa.

Audi should put on bright red letters on the engine saying "FULLY SYNTHETIC OIL ONLY!!! USE OF ANY MINERAL OILS WHATSOEVER WILL CAUSE EXTENSIVE ENGINE DAMAGE!!!"

Most people eventually notice the oil is a bit low, and buy halfrauds or petrol station oil and dont know what kind it is, then top up the car and later it goes bang. It came from the factory filled with fully synthetic and must remain that way!

FULLY SYNTH ONLY AT ALL TIMES if you intend to top it up, or if you get a service / oil change done at an indy, make sure they know this too!

My indy dealer did an oil change using mineral oil, and the traces of synthetic in the system were enough to cause the start of sludging up, a flicker of the oil light occasionally and blackening of the oil showed this to be happening in just 3000 miles.

I poured wynn's engine flush in the motor, then when it was at operating temp I revved it at 2k rpm for 15 minutes (wynns recommendations for full cleaning) and then switched off and dumped the VERY hot oil into a steel container under the car, letting every drop escape before fitting a new oil filter and filling up with 4L of fully synthetic oil at £36 from a motor factor, It doesnt have to be dear, but it DOES have to be fully synthetic. Wear thick waterproof gloves! That old oil will be at about 200deg c. - it has to be dumped hot so it is thin enough to drain completely. I will flush and refill it again at the soonest opportunity so that it is clean and golden and the engine should last a long time.

If you top up or otherwise use normal oil of any other kind and keep running the car, you will get a blown engine in the end....its just a matter of time.

If you have the dreaded oil pressure light already, and your dipstick shows between min and max, then stop using it and get it flushed right away.

The full article I read was from industry experts in motor oil, and I could dig it up for you to read, but take it from me, it is serious.

Hope this helps.
 
i admit i've used semi to top mine up once and it hasnt missed a beat, but i wasn't happy about it as i wouldn't do it to my customer's vehicles and i value my car much more, but i was on my way down south and it beeped and the light came on the dash and freaked out the bird i was with so i stopped of at the next service station but they had no fully synthetic so chucked in a litre of semi. *slaps wrists* but thanks for the info though evil. its good to keep in mind for servicing time for others.
 
Tbh i suspect it was more likely just crappy mineral oil breaking down and causing the sludging than any reaction with the existing synthetic oil

The mineral oil cant handle the temperatures present inside the turbo etc and breaks down, which is why semi synthetic or better is recommended for turbocharged engines.

Audi themselves only recommend a 5w40 semi synth oil for the 1.8T (when not on the longlife service plan) although i always tend to use "fully synth" in mine. I put those quotes there because a lot of "fully synth" oils are infact just hydrocracked mineral oils.
 
I know mine was filled with non synth with a new filter 6 months ago, and when I started to look into the yank posts on 1.8T oil sludge / pump failure issues, I checked the oil, it was black as hell and thick. I was getting the dreaded oil pressure light, did a full flush & synth etc and it has completely cleared up. The oil is still clean tho dark gold colour after 2 months on synth. I stand by what I have said and hope others take the same precautions if they are worried about it.

At the end of the day, why are these ultra modern engines failing in such a dramatic manner? If it isnt the mixing of oils and the use of mineral in a turbo charged engine then what is it? Old worn motors are the bread and butter of the oil trade, where they sell additives and all the different oils which have no real effect on an old non turbo hack. They even recommend against using synth in an old engine as it cleans and dislodges carbon and other deposits that may then block oilways.

If it came to paying even £60 for a gallon of synth, or £3000 for a new engine, I know which one I would pick.

Its up to you!
 
At the end of the day the mineral oil likely caused your problems. The whole point of semi and fully synth oils are that they can better withstand the temperatures and abuse from a turbocharged engine. Stock mineral oil will break down and turn black and sludgy, just like it did.

There are two main things that, imo, kills these engines. 1. Crap oil (ie mineral) or insufficient servicing (or both), the oil becomes degraded and sludgy and blocks the pickup leading to a lack of oil pressure. and 2. High mileage. The oil pump is one of the first components to wear out in a high mileage 1.8T, pressure drops and you get problems, more so when combined with crap oil or bad servicing!

I change my oil every 5k miles and use a "fully synthetic" 5w40 from my local factors, i say "fully synthetic" as it is just a hydrocracked mineral oil, the same as semi synthetic, but with a higher % of synthetic parts to it. It costs £20 a gallon and i feel that using that and changing it every 5k is better than using £50 a gallon real synthetic oil, and changing it every 10k, on a car like mine (B5 1.8T).

If it was a high performance car, ie an S4 or a tuned 1.8T then i might have more incentive to use a proper PAO/Ester based synthetic oil, however i'd still want it changed every 5k miles!
 
This is really useful info. After changing my oil on our B6 TDi 130 for the first time I couldn't believe the state of the so called longlife oil after just 10k miles (and this wasn't mixed with anything other than the spare oil the garage gave me). So I did some reading on different oils etc and there does seem to be a lot of conflicting info on the subject. Some oil companies seem to be suggesting reverting back to semi synth on high mileage engines to preserve the seals. Is this just because they are assuming high mileage = older engine or is there some other justification for doing this?
 
The makeup of the oil shouldn't make a difference in that case Andy, its the viscosity that is the issue, on really worn engines if the oil is too thin then it may not protect the engine components properly as its not thick enough to bridge some of the tolerances, ie hydraulic lifters may not operate correctly due to the oil being too thin to get the pressure high enough.

I always use Mobil 1 fully synthetic, my engine takes 8 litres of oil however and this is a bit costly.
 
Yes that's what they were saying, "fully synthetic can be too thin for higher mileage engines". The car's done 195k miles, so should I be using semi?
 
Whether its fully synth or mineral doesnt affect the viscosity... 5w40 is 5w40 regardless of what makeup the oil has, its an industry standard for a reason!
 
That's right but mineral oil does not normally go as low as synth.
 
ye so as long as you dont fill your clanky old engine that specifies 15w45 oil with some 0w20 synth you'll be fine.

Also the last number is more important than the first in most cases, ie filling an old engine with 5w40 synth instead of 15w40 mineral will make no odds to its seals etc, as the 5w/15w represents its thickness when cold, and both 5w and 15w oils are thicker when cold than the 40 weight they become once the engines warmed up.
 
So to who it applys simply take it off ****** Longlife and service more regular with the SAME oil!!!:applaus:
 
pretty much, the manufacturers service intervals are a balance between the car lasting thru its warranty period, and looking cheap to run to prospective buyers.

If they can say the car will do 15k miles between services and the engines will last thru the warranty period then they'll do that, as the guy buying the car isnt going to care about it in n years time when the lack of oilchanges has damaged the engine irreperably
 
You will NEVER EVER manage to get all the old engine oil out by simply draining the engine. There will always be old oil sitting up in the head and in some of the oilways.

The only way to be sure that all the old oil is out is by stripping the engine down!
 
Flush it through with a 50:50 mix of diesel and cheap engine oil.
 
aragorn said:
ye so as long as you dont fill your clanky old engine that specifies 15w45 oil with some 0w20 synth you'll be fine.

Also the last number is more important than the first in most cases, ie filling an old engine with 5w40 synth instead of 15w40 mineral will make no odds to its seals etc, as the 5w/15w represents its thickness when cold, and both 5w and 15w oils are thicker when cold than the 40 weight they become once the engines warmed up.
Click to expand...


I always thought it was the cleaning agents in synthetic oils that clean the crap away from worn out seals causing them to leak.
 
Just done a bit of checking and apparantly the molecules are smaller in synthetic oil so can leak out where larger molecules in mineral oil cant.
 
If you want to read the article I did, its by a chap called Dr Haas, its VERY long but it was a wet sunday, anyhoo he is a biochemist with a lifelong interest in motor oil chemistry and knows his stuff backwards. He is also an avid ferrari & mercedes owner and puts things in perspective from the owners point of view, not the oil company.

See the full article here - if you get to the end without nodding off you get a blue peter badge! It does explain the problems in detail though, and is a brilliant article:

http://ferrarichat.com/forum/faq.php?faq=haas_articles#faq_motor_oil_basics
 
Jesus, that bloke has ferrari's, lamborghinis and a maybach!
 
LOL yeah he is a surgeon too, and probably earns more than all of us put together!

Certainly knows his **** when it comes to oils though.
 
My car's on a longlife service but I was thinking of changing the oil myself half way through as I don't like the idea of having the same oil for 18k especially with having a turbo!

I was going to buy some Castrol Edge oil 5w/30 from e-bay but I was wondering how much oil do I need to fill it up from empty after the change ?
 
i think its fairly useless to just change the oil , you need 3.5L and a new filter
 
evilscotsman said:
I poured wynn's engine flush in the motor, then when it was at operating temp I revved it at 2k rpm for 15 minutes (wynns recommendations for full cleaning) and then switched off and dumped the VERY hot oil into a steel container under the car, letting every drop escape before fitting a new oil filter and filling up with 4L of fully synthetic oil at £36 from a motor factor, It doesnt have to be dear, but it DOES have to be fully synthetic. Wear thick waterproof gloves! That old oil will be at about 200deg c. - it has to be dumped hot so it is thin enough to drain completely. I will flush and refill it again at the soonest opportunity so that it is clean and golden and the engine should last a long time.
Click to expand...

I don't wish to sound pedantic, but it's unlikely you are ever going to see 200 degrees C oil from your engine.

Current VAG cars tend to have a water/oil heat exchanger which speeds up the warming of the oil when the engine is first used by using the engine coolants higher temperature to warm the oil, then uses the engine coolants lower temperature to cool the hot oil once the engine is working hard.

Even on a track, after 20 minutes, it's unlikely you'll ever see an oil temperature of much over 120 degrees C.

When you warm an engine as advised by Wynns to carry out the flush (it's good stuff by the way) you will be lucky if you are seeing much more than 80 degrees oil temperature.

I've whipped the cam cover off to change cams on VAG engines whilst the car's been strapped to the dyno (not running, obviously!) and after half an hours mapping time and although the oil is damn hot...it's workable after 10 mins or so with laytex gloves on. With 200 degree C oil, you'd have no skin left.


So, if the 200 degrees C isn't going to materialise...people are fine with plastic moulded oil trays!
Just to let people know...
 
ok cheers, was kind of an exaggeration but it was ****** hot! And you can still get a serious burn at 90deg c.

(Ive had 2nd degree burns from boiling water which is obviously at 100deg c and needed extensive hospital treatment. Hot oil is even worse because it clings and doesnt evaporate.)

Anyone who is doing this kind of "hot flush" (lol) should still be very careful and not underestimate just how hot that oil will be - just didnt want people burning themselves, and the filter & its casing does remain over-full even when the engine is drained from the sump, so when you unscrew it, you get a gush of hot oil all over your hands....then you have to try and pull the filter out and not drop it, while its burning you through your latex gloves!
 
I always found it best to have a short run in the car and let it sit for about 10 minutes to allow all the oil to drain back down into the sump before pulling the plug.
 
The filter is after the oil pump. So regardless of how full the sump is you will always get the same amount of oil out of it when you remove it.

i dont know where its mounted on a B6, but on the B5 its mounted under the coolant tank at an angle off the side of the block, and its reasonably easy to hold onto it without covering yourself in oil as you unscrew it...
 
aragorn said:
At the end of the day the mineral oil likely caused your problems. The whole point of semi and fully synth oils are that they can better withstand the temperatures and abuse from a turbocharged engine. Stock mineral oil will break down and turn black and sludgy, just like it did.

There are two main things that, imo, kills these engines. 1. Crap oil (ie mineral) or insufficient servicing (or both), the oil becomes degraded and sludgy and blocks the pickup leading to a lack of oil pressure. and 2. High mileage. The oil pump is one of the first components to wear out in a high mileage 1.8T, pressure drops and you get problems, more so when combined with crap oil or bad servicing!

I change my oil every 5k miles and use a "fully synthetic" 5w40 from my local factors, i say "fully synthetic" as it is just a hydrocracked mineral oil, the same as semi synthetic, but with a higher % of synthetic parts to it. It costs £20 a gallon and i feel that using that and changing it every 5k is better than using £50 a gallon real synthetic oil, and changing it every 10k, on a car like mine (B5 1.8T).

If it was a high performance car, ie an S4 or a tuned 1.8T then i might have more incentive to use a proper PAO/Ester based synthetic oil, however i'd still want it changed every 5k miles!
Click to expand...

I'm with you on this. Mines a TDi and change every 5k or 6 months without fail. I user Millers xfe-pd hi-synthetic oil. Perfect for the PD diesel.
 
Silly few questions but ive never changed my own oil and am going to give it a try this time round.

Do you buy a replacement sump plug and do you use the professional tool to remove the oil filter?
 
in my case, no to both

The original plug seals just fine in my experience and USUALLY i can undo the filter by hand (it shouldn't actually be fitted super tight anyway).

Any oil filter that gives me trouble gets a screwdriver punched thru the side of it and that gives enough leverage to remove it. But that usually only happens the first change i do after buying a car, when some garage seems to have fitted it with a power bar though.

Also, dont go near Audi or halfrauds for your parts. Get the oil and filter from a motorfactors, as the pricing will be a lot more sensible.
 
Aragorn, you can't punch a hole through the filter on a B6 TDi as it's a paper element type which sits in a metal housing. I presume the petrol engines are the same. So you do in fact need the tool, which is only about £7 from GSF. Mine was really really tight, so would not have stood a chance using a ratchet type remover. Always buy a replacement sump plug, it's 50p so why wouldn't you?
 
AndyMac said:
Aragorn, you can't punch a hole through the filter on a B6 TDi as it's a paper element type which sits in a metal housing. I presume the petrol engines are the same. ?
Click to expand...

On the petrol they are metal filters. You can punch a screwdriver through but there isn't much hand room. Best bet if its tight is to buy a tool as they are very cheap.
 
on the B5 its mounted to the side of the block and hangs off the oil cooler at and angle, if you remove the water headertank theres plenty of room. Clearly the B6 may be different, but i think the engines are pretty similar...

As for the sump plug, the audi dealer is a 30mile drive from here, so by the time you add in fuel and time its more than 50p. I buy the oil and filter from a motorfactors thats local to me and they dont stock items like sump plugs for every car so i cant get it there. I've always reused it and its been fine.
 
audi upgrades
I would imagine the filter's in the same place on the B6 and B5 1.8ts.

I do mine from underneath as you have to remove the undertray to drain the oil anyway (never have liked the idea of sucking it out).

The best tool for removing the filter is a strap type like this........
141506220_tp.jpg

There's plenty of room under the engine.
link

Punching holes through oil filters is ****** messy! There's no need to spill any oil because the filter is vertical, the most you'll get is a few drops from the oil cooler when you've removed the filter.

You can reuse the alloy sump plug washers a couple of times but as Andy says the whole plug and washer is 50p odd, so I fit a new one everytime.

As for filters I always use OE in my cars and bikes. The OE oil filter is about £6 from Audi IIRC (I always but 2 or 3 at a time) so why buy pattern? The (tiny) one on my GSXR 1000 about £12!!!

Oil is always an open subject but as we're in the 21st century I always use a good synthetic. I bought a case of Elf Excellium LDX 0w30 (VAG 503.01) a while back and I'm working my way through it! The bike gets Castrol Power 1 Racing. I know that if I don't have a chance to change it it'll be fine to leave in for a bit longer than a lesser semi.

BUB :beerchug:
 
Audi don't actually make the filters, they don't make any of the regular maintenance products, so I always buy Mann filters from GSF which are cheaper than from a dealer but exactly the same.
 
Yes I know they're Mann Filters but I'm a fussy git and like to see the VAG logo on the filter :)

I've a mate that works for GSF up here and a while back they had a job lot of the OE boxed filters, I think I paid about £4 each, but he can't get them now :(
 
oneninet said:
i think its fairly useless to just change the oil , you need 3.5L and a new filter
Click to expand...

Is this right that you only need 3.5L to fill it back up after a change ? Seems on the low side to me!

Can any of you please confirm ?
 
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