Engine Oil. Changing filter only

I’ve got full synth in my 15year old turbo diesel.  In the last 12 months its done 5000 miles.

I’m thinking of just changing the filter and keeping the oil for another year.  Saves me £45 plus the mission of crawling underneath the car on a public road and trying not to spill a drop.

Anybody else take this approach?

If you’re not going to change the oil there’s little point in changing the filter, IMHO.

^ That

BTW – when was the oil and filter last changed?

No, but most of my oil will come out if I remove the filter. Isn’t yours at the bottom?

If it’s only done 5k why do you need to change the filter but not the oil? Why not leave it another 3-5k or whatever the service interval is and do both?

Both or nothing.

I’d do both

My filter is at the top of the engine and pointed downwards so I don’t loose hardly any oil.   Changing the filter is a 5min job.

All my life its been about changing the oil annually. I know modern cars   have a much longer service intervals  but mines a old.  I assume original spec oil would have been mineral.  Full synth is marketed as ‘it doesn’t break down like mineral does’ so surely cares more about 5000k than i does 12 months.  Hence the idea of just changing the filter as it easily done.

Not a lot of point just changing the filter.

I mean it won’t do any harm for the sake of a fiver but it’ll still have whatever contamination in the oil there already is.

I’m thinking of just changing the filter and keeping the oil for another year.

Pointless. I’d consider the other way around, but changing the filter is usually only a trivial amount of extra work / expense.

When you run the engine, the oil picks up water and other rubbish from the products of combustion that leak past the pistons (especially when the engine is cold) and can make the oil acidic. Oils have additives that prevent this and also prevent corrosion to the engine bearings, etc. The additives only last so long before they cease to be effective. An engine that covers low mileage / short journeys / frequent starts are probably more reliant on these additives than one that’s driven regularly for longer journeys that give the oil and the whole engine a substantial amount of time at full operating temperature so that blow-by is minimised relative to miles travelled and contaminants – water, excess fuel, etc. – are driven out of the oil.

One of the reasons for the oil change is to freshen up these additives.

Get a 12v oil extraction pump. An absolute game changer. I bought one after a disastrous oil change a couple of years ago.

I was having an issue with very frequent regens on my Mazda. I got the car up on the ramps, put my 6 litre oil pan under the sump, cracked the drain plug and out the oil came. The oil capacity for the engine is 5 litres so my 6 litre pan should have been more than fine. I’m lying under the car and the pan is rapidly approaching the brim with no sign of the oil slowing down. I panic as I realise the drain plug is somewhere in the hot pan of oil! I had to stick a finger in the drain hole and fish around in the hot oil for the sump plug. Eventually found it and got it back in. Then had to gingerly drag the filled to the brim pan across my monoblocks as oil splashed everywhere. Managed to get it emptied and back under again to get the rest of the oil out. Ultimately about 8 litres thanks to the frequent regens diluting the oil with diesel. Eventually solved that problem by replacing all 4 injectors.

Since then I bought a 12v extraction pump from Lidl in one of their weekly specials. Connect to the battery, one hose down the dipstick, the other hose into a suitable container, turn it on, oil sucked out with no mess. First couple of times I cracked the sump plug just to make sure there was no residual oil in the sump but the pump gets everything out with.

3L is a big difference Bob. Definitely contamination in the oil? My book says 6L, so that’s how much I bought the first time I did it. 8L came out, but that is right, had to go and get some more as it takes 8L to get the level correct on the dipstick. I wouldn’t necessarily believe your 5L, especially if that’s the first time you did it. If you know for sure you only put 5L in then that’s different

Thanks Tillydog – there is no arguing against that.

BoardinBob.  Nightmare!    Off to get a pump – defiantly the way forward.

It’s not just about the miles, engine oil deteriorates over time. The more frequent the changes the better. 6k or 12 months, never mind the extended service intervals which exist to appeal to fleet running bean counters who get shot of the vehicle at 3 – 5 years old.

No point just doing filter as others have mentioned..

Fully synthetic engine oil is good for 20k miles or a couple of years. Leave it alone until next summer ?

if its any help (it wont be), a bloke in work ran a Saab for 100,000 miles and didnt change the oil once. Fairly incredible. car is now dead mind.

Otherwise, i am with the others, do both or do neither.

These pumps sounds intriguing. Anyone got a link to one?

Regarding modern oils lasting 20k miles – I like to keep my ear to the ground on such matters, there seems to be a portion of the trade who think the manufacturer inflate service intervals beyond what is best for the car, because it drives sales and any issues caused are outside their period of liability.

If I change oil and filter – always both – inside the specified time and distance if gives me a warm fuzzy feeling of satisfaction – a form of mechanical sympathy.

Smith and Allan are a good source for oil at a realistic price.

Definitely contamination in the oil

Yeah, absolutely honking of diesel and in retrospect there are three marks on the dipstick. One for minimum oil level, one for maximum and then a further higher X mark that is the threshold for diesel dilution and my oil level was well above even that.

I was getting DPF regens every 20 miles. I spent a few weeks monitoring everything like a hawk via an OBD app. After much research I discovered a random forum where the problem was being discussed and the culprit was identified as failing injectors nozzles causing very poor combustion which was in turn filling the DPF rapidly and triggering the regens. Cavitation of the tips causing poor spray pattern.

Sourced 4 brand new injectors for £1,200 and changed them myself. Problem solved. Regens back up to every 200+ miles and the oil level has been rock solid for the past 2 years

Fully synthetic engine oil is good for 20k miles or a couple of years

In a lab maybe. With fuel contamination. Less so

I do my 3 in use cars every 5k with Mannol synthetic bought in 20l drums cheap from Ebay / Amazon.

My V70 is on 208k miles mainly by us and is sweet as a nut.

I have a Pela vacuum pump but it’s worthwhile getting the ramps out and having a look underneath and touching up the underseal wax / keeping a general eye on things.

These pumps sounds intriguing. Anyone got a link to one?

A random amazon one but they’re all the same. Stick the hose down the dipstick and suck the oil out. When you hear it sucking air give the tube a bit of a jiggle until it sucks oil again, repeat that until it’s only sucking air. The only slight caution is it may not fit all dispsticks. Mine fits my Mazda but I can’t get it into my Abarth so that still needs to go up on the ramps but one is a 2.2 diesel and the other is a 1.4 petrol so it may be smaller engines have smaller dipstick tubes.

https://www.amazon.co.uk/FreeTec-Change-Extractor-Suction-Changing/dp/B0C5MFS5QD

Another vote for both or neither.

and I’m in the neither camp. I’m usually on the side of the preventative maintenance camp, but last year I just couldn’t be arsed to service my car after only 5000 miles. 2 years now since the last service and I’d better pull my finger out now…

In a lab maybe. With fuel contamination. Less so

there seems to be a portion of the trade who think the manufacturer inflate service intervals beyond what is best for the car, because it drives sales and any issues caused are outside their period of liability.

really long service (20k+) service intervals have been around for a decade now. There has not been any increase in 10 year old, 200,000 mile bmw, merc or porsches requiring new engines as a result. Engines outlast the economic lifespan of a car, changing oil less frequently isn’t stopping that – it might be reducing the life from 500,000 miles to 400,000 miles, but very few people care

I use a suction pump on our car when I need to, but not a 12v one, I use the hand-pumped silverline one, and it takes all of 3 minutes to do. I don’t see the additional value that electricity gives for something you’re doing once a year.

I’d also say both or neither.

I bought a Pela suction pump about 4 years ago after a similar encounter to a post above. When doing an oil change on a Bora 1.9 TDI I was using an 8 litre drain pan. I started pannicking after 7 litres of oil came out of a car which should have had around 5-5.5 litres and had to hastily stick the drain plug back in. In my case the tandem vacuum/fuel pump had a split gasket, allowing diesel to dilute the oil. Suction pumps make oil changes easy.

I’ve started using Mannol oil, same as RustyNissanPrarie, it’s often on offer on eBay for less than £15 for 5 litres. I stick with Mann oil filters too, they’re only £1-2 more than the cheaper brands. Our cars are 18 and 20 year old diesels so not worth much, but still need servicing if you want them to be reliable. They get oil changes between 6-8k miles, a lot of which is motorway mileage.

There has not been any increase in 10 year old, 200,000 mile bmw, merc or porsches requiring new engines as a result

Alot more people I know seem to have clattering timing chains on their BMW’s and mercs. Few folk I know have had them jump. Plenty focus/transit/fiesta owners who will attest their engines needing replaced -like wise many stellantis vehicle owners.

Alot more people I know seem to have clattering timing chains on their BMW’s and mercs

The Merc issue isn’t to do with timing chain wear, I don’t think.  It’s to do with the tensioner and the plastic guides. The tensioner leaks oil out, then as the engine starts it is slack so the chain clatters into the plastic guides which eventually break and drop into the engine.  Easy and cheap to replace; removing the engine to access them much less so.  I had my tensioner replaced with an updated one.

I had variable service intervals on my Passat – yes, sometimes it would go 15k miles and 18 months, but another time it only did 6k miles.  It calculates the expected oil stress based on oil temperature and engine stress I think.  The Merc has always flagged a service at 12 months despite only having done 4-5k miles despite being variable – I think it can go more in terms of miles but not time.

Dirty filter filters better than a clean one… sort of.

I’m in do them both or do nowt camp

If you’ve ever had an original Mini with A-series engine then you’ll know that some leak enough to change their own oil with a regular top-up. Occasional oil filter and job done

The front sub-frame never rots as a result, unlike the rear one

My oil gets changed every 5-6k miles.

If there was thing I’d want to do to keep a 15 year old turbo diesel running nicely it would be regular oil and filter changes.

As others have said, changing the filter on it own is a bit pointless – do both or neither.

Note diesel oil generally degrades due to carbon loading / effectively soot from combustion – that is generally proportional to miles driven, so you’re actually likely fine to go off miles rather than time. However – as per my first point regular or over/regular changes are probably the cheapest and most effective way to keep things running sweetly.

Plenty focus/transit/fiesta owners who will attest their engines needing replaced -like wise many stellantis vehicle owners.

There are plenty of design flaws. They aren’t related to service intervals. The ecoboom engine has a 12,500 mile interval anyway

if its any help (it wont be), a bloke in work ran a Saab for 100,000 miles and didnt change the oil once. Fairly incredible. car is now dead mind.

Is that all? When I gave my 1.9TDi Octavia away, it was 19 years old, I’d had it for 15 of those years, and I just topped up the oil when the level dropped a bit low. It had never been serviced. Bloke at work asked if he could have it, ‘cos his son in Poland needed a car. Last I heard, it was somewhere like Lithuania.

Lots of Skoda spares in that neck of the woods. It did need a new turbo…

There are plenty of design flaws. They aren’t related to service intervals. The ecoboom engine has a 12,500 mile interval anyway

12500miles OR (and I know why you elected not to mentioned it) 1 year.

Oh and the leading cause of premature wetbelt failure. -contaminated oil.

Another 20l mannoil drum buyer here.  If its good enough for RNP I’m happy

If its good enough for RNP I’m happy

Apart from engine oil I use Mannol in differentials (75/90w) and autoboxes (3309). Its been in my Volvo autobox for a few years and recently in my Cayenne. Shift quality improved measurably but only because the Porsche service schedule is 160k for gearbox oil change.

The other issue with long duration oil changes is that the engine breather/crankcase ventilation systems get clogged when the oil is saturated with contaminates.

5lab

really long service (20k+) service intervals have been around for a decade now. There has not been any increase in 10 year old, 200,000 mile bmw, merc or porsches requiring new engines as a result.

Is this from published data or your personal experience? Not a criticism, just curious because I could never find anything concrete.

Never heard of Mannol before – anyone know why’s it so much cheaper?  It’s about half the price of Halfords own brand oil!

There has not been any increase in 10 year old, 200,000 mile bmw, merc or porsches requiring new engines as a result.

Maybe not new engines, but on modern Euro 6 diesels and the impact of the emissions gubbins on oil degradation, I would not fancy running the same oil in a diesel for 20k miles. I change mine every 6k, either doing it myself or the garage as part of the annual full service. Spending £45 on oil and a filter once a year is a lot better than the outlay for a new EGR, DPF or turbo, all of which are very common on my engine for those that follow the normal 12k service interval.

modern Euro 6 diesels and the impact of the emissions gubbins on oil degradation

Explain further?

Explain further?

Google has lots of info.

A taster -although I know your asking to be obtuse and you have a fair handle on the subject.

https://www.sciencedirect.com/science/article/abs/pii/S0043164807003742

Explain further?

regens inject extra fuel – some of this especially when the regen aborts/fails finds its way past the piston rings into the sump which dilutes oil.

Oil viscosity is lower nowadays for improved efficiency (although oil performance has improved), diluted oil leads to mains and big end bearing wear.

My D5 Volvo engine has two XX’s above the normal oil dipstick level to allow for dilution before the engine flags a warning to change the oil. Until it does that those bearings are running in piss water oil.

E10 fuel exacerbates the piston ring issue also as not all of the fuel is burnt in the cycle and it washes into the sump Making your oil corrosive to any seals in the mix.