My Superb 1.9TDi 130 is now 26 months old with 81,000 miles on it. So out of warranty.

I will be doing my own servicing and hope someone can say which oil gives that longest between servicing.

Reading the parameters from the Instruments I get

40 distance since last service = 27700km

41 time since last service = 152 days

47 soot in oil equivalent to = 41100km

48 thermal load equivalent to = 13000km

This means that even though I have been treating the engine gentle ( mileage equivalent of thermal load less than actual mileage ) the oil is degrading much quicker than the real mileage ( about 1 1/2 times quicker ! )

I am assuming that the stealer put in a sub-standard oil ??? ( Anyone know what the dealers are using these days ) Or maybe my engine needs retuning ?

If so is anyone past 25000km since last service, know what oil they have in, and can give their readings for channels 40, 47 and 48 when entering the instrument module.

It would be nice to get the full 50000km between services ( I did it in the past with my Octavia 1.9TDi 90 using Castrol SLX II long life ). Hopefully just a case of choosing the right oil.

Thanks all in advance of you replies

Langtone:

i THINK YOU HAVE TO USE SPECIAL "pd" OIL FOR THESE ENGINES otherwise they go "pop"!

Sorry no more info than that (and apologies for caps!)

The oil put in at the last service was done the dealer at its last service. If they have done the job right this will be the long life PD compatible oil conforming to VW 506.01

I top up using "COMMA Fully Synthetic 0w-30 Long Life Motor Oil" claiming to meet 506.01 506.00 and 503.00. Probably topped up 3/4 litre since the service done 17300 miles ago

So the question I have is this :

Assuming I am buying a 506.01 spec oil. Will I get longer between services if I buy Shell, Comma, Castrol, Total OR Millers ( or one of the others claiming to be 506.01 ) ?

One thing is obvious between Castrol and Comma - the castrol oil 'clings' more than the comma and even though they both claim to be the same viscosity the Comma pours faster ( and probably less important is a much clearer colour )

Which oil will keep the Soot mileage value closer to the real mileage value and allow running up to the 50000km maximum ?

**** Knows!

The soot is down to the additive package used in the oil.

Some of these are for lubricity, some are for break down resistance, some for neutralising acids and others for locking the soot up and making sure it doesn't block things.

I always found Millers old school engine oils came out a lot cleaner than the Castrol GTD magnatec, on my old dervs, however that's purely a finger in the wind value.

I would suggest that the fuel you use will probably have more of an effect on the soot build up in combination with your air filter than the oil.

Eg fuel that doesn't burn properly == soot

I can tell you straight off that the 40k air filter change is a joke, and if you don't change the air filter more regularly than this, it come out blacker than a black thing on a very dark night, and chocked full of dirt.

This lack of enough air to burn the fuel completely at higher revs, combined with a lower quality fuel will result in more soot than usual.

Oh and the other nice thing about the millers is that the XF Long life comes in 5l bottles, although i have no idea how much oil the 2.0TDI takes as yet.

Thanks Cheezemonkhai,

The air filter was changed last at 44000 miles, so 37000 miles ago.

I'll have a look at the filter tomorrow. Maybe I just change it anyway, there is no rule saying you must change the air filter when you do an oil change and they are pretty cheap in comparison to the cost of the oil. I have the filter already.

Now I'm servicing myself I was going to change the air filter each oil change so hopefully get less soot in future regardless of oil.

Anyone else used / recommend the Millers Oils XF Long Life ?

I totally agree about the air cleaner change interval - mine was nearly choked at 20k miles and the housing full of dirt. The engine ran noticably better with a new element. I would change the fuel filter every 20k too, and drain the water out of it (tap fitted - although a bugger to get to) every 10k at least. The dealers don't do this.

The monitoring system on the B5.5 is not very sophisticated and doesn't measure oil soot or thermal loading - these are derived quantities from the number of cold starts, oil temperature, etc. All diesels will make the oil sooty and the detergents in the oil will keep the soot suspended and therefore harmless. The oil filter will remove any particles which are too large. The only way to have "clean" oil on a diesel is to fit a bypass filter as used on larger commercial diesels.

You can't tell anything about an oil subjectively unless its grossly unfit for use. Stick rigidly to the VAG specs (not doing so will wreck the unit injector cams and roller followers) and change the oil at least every 10k miles. Their "extended" service intervals are for the fleet market and will not do the engine any favours. If you want the very best economy from cold, use 506.01, otherwise 505.01 is fine for 10k/annual changes.

The only use I found for variable servicing was to keep a car which is under warranty out of the dealer's hands - the oil will come out as soon as the warraty expires.

rotodiesel.

The monitoring system on the B5.5 is not very sophisticated and doesn't measure oil soot or thermal loading - these are derived quantities from the number of cold starts, oil temperature, etc.

rotodiesel.

Thanks Rotodiesel,

If the engine is really NOT monitoring the oil soot, but deriving it from temperature and startups, then the oil could actually be worse than the soot value !

OK. I was intending using the best of the best oil, letting it run as long as the engine monitoring said it is still good oil.

BUT if the engine really does not monitor the actual oil I would much rather go to the 10K service.

I'll probably still stick to the 506.01 though. I am sure the extra additives will not hurt, and knowing the oil will still be in good shape as it will only have been in for half the time it was designed to work to.

Anyone have any comments as to whether Millers is the best ?

I always used Millers in the Octy I had previous to the Superb, which I had on variable servicing and so used Castrol long-life stuff. Now it's no longer under warranty I have had the car switched over to 10k servicing, and use Miller XFE-PD and not long life stuff. I have read somewhere that long-life oil wasn't so good if on fixed/annual servicing, but that I find strange.

I've been to two Skoda dealers, who have told me Variable servicing is based on oil quality, and if it detects any impurities, it brings up the service reminder...

Ask you dealer(s) where the transducer is which measures the oil "quality". The Hella monitoring unit screwed to the bottom of the sump measures oil temperature and oil level. Then find a decent dealer - if you can.

rotodiesel.

Yeah there is only so much the engine can measure and only so much crud an oil can hold out of the engine.

Personally I'd go for a Millers XF longlife (0w-30 = 506.1) or (5w-30 = 507.0), and run it for about 10-15k then change it when servicing myself.

As rotodiesel (why name yourself after a lucas fuel pump? - not that I can talk ) said at the same time change the air filter, and if you can do it the fuel filter should be drained too.

Thanks all,

I'm convinced. No one is suggesting running an extended service interval once out of warranty. So I'll do the full service on Saturday - Oil, oil filter, air filter, oil filter ( change as I am not convinced it got changed at 40K ). I'll take a picture of the air filter so others can see what a filter after 37,000 miles looks like

If the engine is not monitoring the crud in the oil then I do not want to risk having oil in for more than 10,000 miles. This is the best car I ever owned and I intend to keep it whilst it looks after me ( whilst reliable ) so why skimp on oil changes.

My original question assumed the car was more clever ( and yes I had been told by a dealer that the oil is monitored by the engine management ) so I thought that I could do the engine no harm or shorten its life by allowing it to say when the oil was starting to loose its full effectiveness.

Kentish ( post #9 ) has heard that if running on fixed servicing it is better not to go for the longer life oil. Can anyone else confirm or add reason why ? ( maybe it is just that the oil is good for 15K and it is not unless pushing further you ever see any difference, so just a question of extra cost for something that you don't see any benefit from 'til later in the oil's life ??? )

I would personally pay the extra for the extended life oil, as that way you can make a change wait if the timing is inconvenient and then change is at somewhere between 10 and 15k rather than spot on.

The 506.1 isn't that much more than the (505.1??) fixed interval stuff I don't think, but I could be wrong.

Difference in cost between fixed service oil and extended is about a tenner

So the cost is 1p every 10 miles, so about 100th of the cost of fuel. Not an issue really.

Here's what I will do:

I will do the service using the long life oil. I will reset the service channels ( 40-48 ) as though I were still on the 'variable service'.

I will repeat this every 10K or so. If I overrun 2 or 3K it will not matter. If I ever sell the car it will still be on variable servicing should the new owner want this ( they may if they allow the stealers to do the servicing )

By the way, just changed the air-filter. Unbelievable the difference in responsiveness. That will be changed at each service, 40K is much too long as the difference in performance is obvious when fitting a clean filter. Will be interesting to see if the mpg is better when I go to Leeds tomorrow.

Yeah by the time my 1.9 TDI had got to 37k i had lost 10MPG. Changed the air filter with a genuine one from a main dealer and all was back up to where is used to be. Stunningly bad as I will have saved that £10 back over a couple of tanks of fuel, never mind the other issues it caused.

You got a pic of the air filter just so others can see how absolutely filthy it is when we say bad? I've never seen anything remotely approaching how dirty this was in all the years of servicing cars myself.

EDIT: Don't know if i said but my local Motor factors have 5 litres of Millers XF Long life for £40 which is less than 4 litres of edge

System and method for determining oil change interval - US Patent 6253601

That might be interesting to some on here too although it sounds a bit after VW released the first variable service motors.

You got a pic of the air filter just so others can see how absolutely filthy it is when we say bad? I've never seen anything remotely approaching how dirty this was in all the years of servicing cars myself.

See attached

That looks depressingly familiar - mine was just the same. Seeing this sort of thing calls into question the VAG maintenance schedule for their cars. In my view variable servicing is a con for the fleet market and does nothing for the owner who pays his own bills.

I see you've found the "Superb" Haynes manual. Most of it is correct and some of it is quite useful. Take the wiring diagrams with a pinch of salt and keep the front suspension pinch bolts free.

rotodiesel.

That looks a lot cleaner than mine was! :eek: :eek:

Mine was proper proper black such that every fin was pretty much black too

Either way, not good.