I checked the oil in my 22,000 mile 1.9TDi this weekend and as expected it hasn’t used a drop. 7,500 miles since it was serviced when I bought it last July and the level has barely moved.

This led me to thinking – I am on the variable service and it currently tells me the next service is due in 5,300 miles. It looks as though I will not need to add any oil before then.

There have been several threads relating to oil usage and others asking whether the fixed or variable service is best for them but here is a new perspective!

If your engine uses, say, 1 litre of oil every 5k miles then over 15k-20k miles between variable services your engine has had 3-4 litres of lovely fresh clean new oil so between services your engine has had a significant partial oil change.

Mine hasn’t! At service time the oil in my sump will still be 100% original.

If the variable service wizardry is measuring oil condition then it will be calling me in for service before the guys who have to top up their oil.

Not sure how it works out but maybe using oil does in fact have some payback in longer service intervals.

With only 12,800miles between variable services I reckon I may be better on the fixed unless I decide to stay on variable for the convenience of an extra couple of months between visits to the dealer – the less they get their hands on my pride and joy the better!!

I checked the oil in my 22,000 mile 1.9TDi this weekend and as expected it hasn’t used a drop. 7,500 miles since it was serviced when I bought it last July and the level has barely moved.

This led me to thinking – I am on the variable service and it currently tells me the next service is due in 5,300 miles. It looks as though I will not need to add any oil before then.

There have been several threads relating to oil usage and others asking whether the fixed or variable service is best for them but here is a new perspective!

If your engine uses, say, 1 litre of oil every 5k miles then over 15k-20k miles between variable services your engine has had 3-4 litres of lovely fresh clean new oil so between services your engine has had a significant partial oil change.

Mine hasn’t! At service time the oil in my sump will still be 100% original.

If the variable service wizardry is measuring oil condition then it will be calling me in for service before the guys who have to top up their oil.

Not sure how it works out but maybe using oil does in fact have some payback in longer service intervals.

With only 12,800miles between variable services I reckon I may be better on the fixed unless I decide to stay on variable for the convenience of an extra couple of months between visits to the dealer – the less they get their hands on my pride and joy the better!!

Hmm; I can 'see where you are coming from' on this one (although took a bit to work it out). Good theory.

I haven't a clue what the answer is though.

For my experience (vRS TDI) I'm just on 16,000 miles from new and service has consistently been predicted to be at 18,750 miles. I topped up with 500ml of oil at 3, 6 and 9,000 miles but have since then topped up with 250ml at each of 12 and 15,000 miles - total 2 litres. I don't expect to add any more before service.

On this basis I would expect to top up at 250ml per 3,000 miles after service at 18,750; will I get to 37,5000 miles for the second service? Wait and see.

Hmm; I can 'see where you are coming from' on this one (although took a bit to work it out). Good theory.

.

Sorry! It was a bit of a ramble!

Just to add to the musing though! Some time ago there was another thread on running-in method vs oil consumption with a link to a URL suggesting that "fast and furious" was a better running-in method than "slow and gentle" because it resulted in lower oil consumption.

Maybe Skoda et al recommend the "slow and gentle" to ensure that you do have a little oil consumption to enable an extended service interval by giving your engine a steady introduction of fresh clean oil between services.

Takin' me anorak off now and gettin' back to work :D

Having owned diesel TDI Octy's over the last six years,that do about 70,000 miles a year, the average top up between sevices is 1/2 to 1 litre between 10,000 mile oil changes. Change it every 10,000 miles, not 12,oil degrades over time and distance.Change the air filter while your at it,at 10,000 miles it's getting "grubby" and it only cost's about £10 or so.

Some years ago I came across an American site where they were testing a 100% synthetic oil - Mobil for starters and then on to Penzoil - I think.

On a monthly basis they took a sample and had it analysed for engine wear products and viscosity changes. Over m any miles and months they came to the conclusion that, provided there were regular filter changes, one could keep the oil indefinitely. Testing of the oil required about half a litre to be removed for analysis and thus replaced with fresh oil. A regular filter change would do the same thing.

It was the constant addition of fresh oil that was the main cause of such long life. The fresh oil topped up the viscosity enhancers and detergents.

It could follow that constant topping up due to oil being consumed by the engine does a similar job.

Is anyone aware what parameters the engine oil quality sensor is actually

looking at?

Checked for the site and I'm sure you will enjoy reading all about it at:-

Synthetic Oil Life Study

It wasn't Penzoil but Amsol.

I am on the variable interval in my 53 Octavia, and I get approx 30,000 miles between oil changes. However the car is quite thirsty, it will soak up a litre of oil over that time. I have had the car for 5 years and it has been fairly consistent over that time.

For reference I do mostly motorway driving, and average 30,000 miles a year.

Whoops - This is the Octavia II forum, I have Octavia I