Viscosity of oil

[Buckman]

In September last year we had a service done at the dealership and this included an oil change. The oil needs to be changed every 12000 miles or every year. I have had a message come up on the dashboard stating that an oil change needs to be done however the vehicle has done less than 6000 miles since the oil change was supposed to have happened.
I phoned the dealership who have stated that perhaps the technician forgot to reset the oil change indicator or perhaps the car has detected that the viscosity of the oil has changed. Also that another issue could have caused the message to come up. It is not a warning message that stays lit on your dashboard. The oil level is okay and the colour of the oil is black however on a diesel the oil colour changes to black quite quickly.
Is there any way a layman can check the viscosity of the oil as do not want to do a 150 mile round trip to the dealership? If not, can a local garage check the viscosity of the oil? Thanks.

 

[RogerL]

There are oil analysis companies that you can send samples to but they aren't cheap in the UK, unlike America where they're very cheap.

If you had a service done in September last year, and it needs changing every year, just have it serviced locally as it's almost due anyway - you can go a month or 1,000 miles over the indicated time/mileage.

 

[Buckman]

There are oil analysis companies that you can send samples to but they aren't cheap in the UK, unlike America where they're very cheap.

If you had a service done in September last year, and it needs changing every year, just have it serviced locally as it's almost due anyway - you can go a month or 1,000 miles over the indicated time/mileage.

Is it not possible for a local garage to check the viscosity of the oil in some way just to check that it is still okay. We have a fully paid for service contract with the dealership and an oil change even at a local place will set us back about £120 and then the dealership will change the oil again in Sept. Between now and end of September we will probably do another 1500 miles.

 

[RogerL]

Oh the pitfalls of buying from a distant dealer - if it were me, I'd assume the technician didn't reset the counter properly last time and have it serviced on schedule - if you're really concerned about the oil viscosity, have it serviced early at your selling dealer.

 

[otherclive]

In September last year we had a service done at the dealership and this included an oil change. The oil needs to be changed every 12000 miles or every year. I have had a message come up on the dashboard stating that an oil change needs to be done however the vehicle has done less than 6000 miles since the oil change was supposed to have happened.
I phoned the dealership who have stated that perhaps the technician forgot to reset the oil change indicator or perhaps the car has detected that the viscosity of the oil has changed. Also that another issue could have caused the message to come up. It is not a warning message that stays lit on your dashboard. The oil level is okay and the colour of the oil is black however on a diesel the oil colour changes to black quite quickly.
Is there any way a layman can check the viscosity of the oil as do not want to do a 150 mile round trip to the dealership? If not, can a local garage check the viscosity of the oil? Thanks.

If the technician forgot to reset the service oil change indicator wouldn't it have come up sooner than this based on time interval? Strange I've not known cars check oil viscosity. My Volvo XC70 D5 would indicate if its oil level increased but that would be due to dilution by fuel. It never happened to me but some owners had the fault. It was caused by incomplete regeneration of the DPF. Volvo sent out a recall. It comprised reducing the quantity of oil in the sump and tweaking the electrons to think the sump with its reduced level was at the correct level. Hence leaving space for some diesel. Priceless.

 

[Buckman]

If the technician forgot to reset the service oil change indicator wouldn't it have come up sooner than this based on time interval? Strange I've not known cars check oil viscosity. My Volvo XC70 D5 would indicate if its oil level increased but that would be due to dilution by fuel. It never happened to me but some owners had the fault. It was caused by incomplete regeneration of the DPF. Volvo sent out a recall. It comprised reducing the quantity of oil in the sump and tweaking the electrons to think the sump with its reduced level was at the correct level. Hence leaving space for some diesel. Priceless.

Good point about re-settting. In the previous year between Sept 2019 and Sept 2020 the vehicle only did about 6000 miles so add that to the current 6000 miles for Sept 2020 till now and total is approximately 12000 miles. Does seem like they forgot to do the reset.
It was the dealership that told me over the phone that the car can check the viscosity of the oil something I never knew that it could do and it is not mentioned in the owners manual. It uses SAE 5W-30 oil. Seems that the dealership reprenstative was telling porkies!

 

[JTQ]

If modern enough a vehicle to have a DPF, and given what this last year has been, it might just be true and reflect excessive oil dilution?
The lockdown has meant many of us have not had the runs to get natural DPF burn throughs and probably any number of aborted, excess fuel powered burns.
This results in oil dilution from the bores, a well-known issue, one of serious proportions with some models, mainly those with non close- coupled DPFs. Those where the DPF was an add on, not originally planned, so older platform designs and those designs with primarily gasoline powered origins.

A locally done or diy, decent change with a low ash oil, not bothering with the filter ought to come way less than £120 and will ensure things don't go way more seriously wrong than "£120sworth".
If that does not cure it then there is another issue to be sorted at the service, but a common, expensive, oil dilution one it is not.

Things are not helped for those of us with big capacity diesels, where running solo it is so lightly loaded the temperature to naturally burn is too low, and being low the combustion is far from optimised.

This last year, with little caravanning, I have made a point to drive ours hard and long, simply to try and avoid having too much light loading, without the van to double up the mass being lugged about.

 

[Buckman]

If modern enough a vehicle to have a DPF, and given what this last year has been, it might just be true and reflect excessive oil dilution?
The lockdown has meant many of us have not had the runs to get natural DPF burn throughs and probably any number of aborted, excess fuel powered burns.
This results in oil dilution from the bores, a well-known issue, one of serious proportions with some models, mainly those with non close- coupled DPFs. Those where the DPF was an add on, not originally planned, so older platform designs and those designs with primarily gasoline powered origins.

A locally done or diy, decent change with a low ash oil, not bothering with the filter ought to come way less than £120 and will ensure things don't go way more seriously wrong than "£120sworth".
If that does not cure it then there is another issue to be sorted at the service, but a common, expensive, oil dilution one it is not.

Over the past 3 months we have done a couple of long trips towing the caravan so assumed that this would have cleaned the DPF. I am not a mechanic so unknown territory to me.

 

[JTQ]

Over the past 3 months we have done a couple of long trips towing the caravan so assumed that this would have cleaned the DPF. I am not a mechanic so unknown territory to me.

It should help a lot, particularly if you made it work hard as often as you could.
If the vehicle is of any great value, I would not hesitate having a fresh oil charge done, even just to get to the planned service.
IMO, doing that will be cheaper than having the oil tested.

 

[Buckman]

It should help a lot, particularly if you made it work hard as often as you could.
If the vehicle is of any great value, I would not hesitate having a fresh oil charge done, even just to get to the planned service.
IMO, doing that will be cheaper than having the oil tested.

True. Making a booking to have oil changed as cheaper than £1200 for a repair.

 

[Robert_374373903]

Our Skoda is on variable meaning when the oil deteriorates the warning light comes on, however the same oil is used for annual as well as variable which to me does not sound right. Myself I have kept to variable until this lockdown and as mileage has fallen we do a annual .

 

[EW1999]

in Russia there is a saying: "you cannot spoil the porridge with butter" following the saying, I think it will not be a violation of the warranty, self-replacement. even if it is a waste, it is a good prophylaxis for the engine. It is very important to replace the filter at the same time as new oil.

 

[RogerL]

Our Skoda is on variable meaning when the oil deteriorates the warning light comes on, however the same oil is used for annual as well as variable which to me does not sound right. Myself I have kept to variable until this lockdown and as mileage has fallen we do a annual .

VW Group cars use an electronic algorithm which tracks the number of cold starts and uses that to trigger warnings when long life variable servicing is used - as my Touareg isn't used every day it would allow me to exceed the nominal time/mileage on variable servicing - although I have it on fixed interval anyway.

There was a time when Variable oil change used a higher spec oil than fixed servicing but under recent emission regulations , the spec for fixed serving was raised and now VW Group cars use the same for both.

General consensus is that long life variable servicing is for company fleet cars to reduce their costs with fixed interval servicing recommended for private users, particularly if they plan to keep the car outside warranty.

 

[ProfJohnL]

It certainly true that some cars can "test" their own oil and will use the information to decide when to call for a service. I have heard of two methods, one uses the opacity of the oil, and the other the electrical resistance. Their may be other methods also. But I can't tell you which cars do it.

It doesn't have to be the garage failing to do the job either, as others have pointed out if they had failed to reset the service indicator, it would have come on much sooner. Given the symptoms, its more likely they didn't do the oil change. But that also is unlikely given the work sheets main dealers have to use.

But equally it could be the oil in the engine has deteriorated and triggered a warning.

Just becasue a the oil is changed at a given service interval, it doesn't mean it will necessarily last for 12months especially if there is another problem brewing inside the engine.

Whilst towing might help to clear DPF's, it also puts a lot more strain on the engine and will accelerate wear.

 

[littlebasher]

Other, more sinister reasons, could be due to the oil being diluted by diesel fuel.

Frequent DPF regeneration can lead to this. where excess diesel is injected to get the DPF nice and hot. Inevitably, some of it finds its way into the oil.

Is the oil level normal, or above the full line on the dipstick.

 

[JTQ]

Whilst towing might help to clear DPF's, it also puts a lot more strain on the engine and will accelerate wear.

How many of us these days wear out our car's diesel engines?

I suggest strain related "wear" is not an issue we need get concerned about.

On the contrary, lack of as you put it "strain", brings far more issues, not least wearing things out from the fuel dilution of the lubricating oil. Then there is bore glazing and turbo vane sticking from carbon build up, all linked to not being worked hard enough.

IMO, we typically don't work our domestic diesel car engines hard enough, so get more issues in our modest mileages than those that work diesel hard, the white van man, and rep.

 

[RogerL]

It's good to "exercise" a turbo-diesel engine and avoid the tendency to always run at part-throttle - towing helps but I suspect few of us spend very long at full throttle, if only because speed limits still need to be observed!

 

[Jcloughie]

I find ATS fair and reasonable. Their oil and filter change start at £45. I think a large engine with fully synthetic might be £65-70.

Might be worth the expense if you are thinking that perhaps it was not done properly last time.

John

 

[otherclive]

VW Group cars use an electronic algorithm which tracks the number of cold starts and uses that to trigger warnings when long life variable servicing is used - as my Touareg isn't used every day it would allow me to exceed the nominal time/mileage on variable servicing - although I have it on fixed interval anyway.

There was a time when Variable oil change used a higher spec oil than fixed servicing but under recent emission regulations , the spec for fixed serving was raised and now VW Group cars use the same for both.

General consensus is that long life variable servicing is for company fleet cars to reduce their costs with fixed interval servicing recommended for private users, particularly if they plan to keep the car outside warranty.

I switched my Skoda from variable to time/ mileage dependant. Ie 12 months or 10000 miles whichever came first.

 

[otherclive]

Other, more sinister reasons, could be due to the oil being diluted by diesel fuel.

Frequent DPF regeneration can lead to this. where excess diesel is injected to get the DPF nice and hot. Inevitably, some of it finds its way into the oil.

Is the oil level normal, or above the full line on the dipstick.

That’s not a sure fire diagnosis for an older engine as if the engine burns some oil the addition of fuel dilution caused by poor dpf regeneration can compensate so the sump level stays okay. The OP should just get a oil and filter change to get to the annual service. Or bring it forwards.

 

[otherclive]

It's good to "exercise" a turbo-diesel engine and avoid the tendency to always run at part-throttle - towing helps but I suspect few of us spend very long at full throttle, if only because speed limits still need to be observed!

It’s like the generalised advise to carry on driving above 2000 rpm for 20 minutes if the car needs a regeneration of the dpf. In my last two diesels that would have been neigh on impossible even on a motorway unless dropping down a couple of gears. Locally not a chance. Non close coupled dpf are the more difficult to manage. The later WVM vans have close coupled dpf as do the new Discovery/Defender as folk will use them for short journeys in cold weather. When my Skoda became problematic in non engine areas we decided to change to petrol and both our cars are now petrol. But even so pre diesel habits of minimising short journeys still remain. We don’t want the white gunk clogging the motors. Roll on electric. 🙈

 

[JezzerB]

And of course new petrols have ppfs!! We;ll see what issues they bring-hopefully none. Our Navara states 12500 or 2 years servicing but a bit like you the oil service light popped up at 10k ish miles-this is from brand new-the servicing garage said pretty much the same as the others the car monitors use-heavy use or lots of short trips -we do both of course-caravan towing for a long distance and short trips interspersed, bring forward the oil change. We got it serviced when the indicator said even though I'd already changed oil and filter at 5500k miles myself-always do it yearly as a minimum-but didn't reset the oil /service meter so the warranty stays intact and is down to Nissan. It's just insurance. The Nissan clearly doesn't monitor oil condition-more type of use ie length of journey etc.

 

[Buckman]

It certainly true that some cars can "test" their own oil and will use the information to decide when to call for a service. I have heard of two methods, one uses the opacity of the oil, and the other the electrical resistance. Their may be other methods also. But I can't tell you which cars do it.

It doesn't have to be the garage failing to do the job either, as others have pointed out if they had failed to reset the service indicator, it would have come on much sooner. Given the symptoms, its more likely they didn't do the oil change. But that also is unlikely given the work sheets main dealers have to use.

But equally it could be the oil in the engine has deteriorated and triggered a warning.

Just becasue a the oil is changed at a given service interval, it doesn't mean it will necessarily last for 12months especially if there is another problem brewing inside the engine.

Whilst towing might help to clear DPF's, it also puts a lot more strain on the engine and will accelerate wear.

Thank you for the input. The vehicle also has a "Service due" message come up when the vehicle reaches the 12000 mile since the last service. This is the first time I have seen the "Oil Change due" message.

The vehicle is on a 3 year service contract plan with the dealership. We took the vehicle for its 8th year or 100,000 mile service in Sept 2020 although it had only done about 60000 miles. This is a major service. However instead of the major service they did a minor service based on the mileage instead of year and the basic service is supposed to be an oil change. After a bit of an argument they agreed to do the major service.

There was also another issue regarding an error message that disappeared before the car was submitted for the MOT. The error message would have resulted in a Fail. Error message came back on shortly after the MOT and service was done. Another argument and it was agreed to replace the faulty item under the service contract. This was one of the reasons why we had a service contract.

The vehicle is very sensitive to any issues and will trigger a warning if there is any other issue. It has had dealership service from day one and we have all the records even though we bought it second hand.

 

[RogerL]

It’s like the generalised advise to carry on driving above 2000 rpm for 20 minutes if the car needs a regeneration of the dpf. In my last two diesels that would have been neigh on impossible even on a motorway unless dropping down a couple of gears. Locally not a chance. Non close coupled dpf are the more difficult to manage. The later WVM vans have close coupled dpf as do the new Discovery/Defender as folk will use them for short journeys in cold weather. When my Skoda became problematic in non engine areas we decided to change to petrol and both our cars are now petrol. But even so pre diesel habits of minimising short journeys still remain. We don’t want the white gunk clogging the motors. Roll on electric. 🙈

DPF regeneration doesn't need 2,000 rpm, that is an urban myth - on holiday I often cruise at 50 solo on ordinary single carriageway roads, about 1,250 rpm in top gear, but it'll carry out an active regeneration if it needs to.

 

[otherclive]

DPF regeneration doesn't need 2,000 rpm, that is an urban myth - on holiday I often cruise at 50 solo on ordinary single carriageway roads, about 1,250 rpm in top gear, but it'll carry out an active regeneration if it needs to.

I did say that it was “ generalised advice” which you can find on numerous motor forums. I didnt say that I agreed with it as with modern diesels it’s “ neigh on impossible”…….