Anybody know how to read the level of oil dilution? One of my colleagues Disco 5 has just had an engine failure on his Td6 after 25,000 miles from new

My Td6 Vogue only goes on long journeys so I am hoping DPF regeneration cycles are unhindered but it did get me wondering if there is a way to check oil dilution on the car so that I can decide if an interim oil change is required?

I have covered 53,000 miles in my 2017 Td6 Vogue and have therefore had short calendar based intervals on the servicing but have of course done the miles..

Assume the Disco 5 Td6 is the same as the Vogue's in 2017?


Thanks in advance! 2017 Range Rover Vogue V6 Diesel
2006 Range Rover Vogue V8 Diesel - gone

I understand that the software for the service indicator measures the oil dilution and will indicate that a service is required if the dilution level is outside the acceptable range

I am not convinced it measures it rather than calculating the likely value. Having an issue on the wifes disco sport having the service interval for the 4th time in just over a year :O. Current: RR L322 2010
Past: RR L405 2017, RR L322 2012, 2008 & 2004, 2018 D5, 2016 Defender, 2011 D4, a few Disco2s, P38, RR Classic, couple of Disco1's, SIII SWB

Do you use Shell oil ?
The reason I ask.... Shell UK offer an oil testing process , where by sending in a sample of the used oil they will analyse it and report back by email the test results.

Click image to enlarge

ianmacd wrote:

I am not convinced it measures it rather than calculating the likely value. Having an issue on the wifes disco sport having the service interval for the 4th time in just over a year :O.

Absolutely. If you want the dilution figure, you’ll need to get a sample of oil analysed. All the car does is count the number of times that the engine’s stopped mid regen and then guess the level of dilution from there.

There seems to be no connection between oil change frequency and crank failure on V6’s (this subject has been done to death on Disco 3/4), it just seems down to chance

My understanding is that a software upgrade last year was responsible for increased frequency of services being indicated because it increased the sensitivity of the system to oil dilution.. Certainly this is what I was told by Land Rover customer services.
When mine indicated that it needed a service the dealer checked the oil dilution percentage to confirm this. I am not sure how the percentage was checked but that is what they said they did.

The condition of the oil as regards dilution is not actually measured on the car.
The dilution level is determined using an algorithm which takes into account various inputs from the car.
As far as I can determine the dilution rate is at best a calculated or educated guess and may or may not reflect the true condition of the oil.

How on earth manufactures now produce cars with engines that dilute engine oil with diesel fuel if they are not driven in a certain manner is beyond me. The fact it now seems acceptable to drive a car with diesel contaminated engine oil seems bizarre to me, given the effort that goes into producing quality oils.

Even more bizarre is the fact that LR have now issued guidance to sales staff to determine the driving styles of new customers in order to allow them to decide if the potential customer should really be allowed to buy a particular car ie a diesel car with a dpf.

Personally I hope not to have to buy a diesel engined car in the future probably going to petrol, but even petrol cars are likely to have to be fitted with dpf's in the near future.

It never ends.

For info,

I get "Service Required" when I start up but the car was fully serviced only in January this year and has done only about 8k miles since then. Given the uncertainty (there doesn't seem to be a reliable way of knowing if the oil is compromised) is it simply best just to get the oil changed or am I missing something.

Or should I just ignore the message?  Geoff

In the last 5 years I have run 2 x RRS L494, 1 FFRR TDV6 3.0, and now a FFRR 4.4. All have been back to the dealers with service required messages on average every 3k miles and all have been under warranty. Bar the 4.4 all the other vehicles have had, under request, the oil dilution levels checked and apparently each time they were within tolerance under 6.1pc. Various software updates were carried out to reduce the dpf sensor sensitivity (to no avail) and no oil changes were carried out.
Only the 4.4 which was purchased from a different dealer, received an oil change without any request. Their service dept said they carry out oil changes automatically when the service message comes on prematurely.

supershuttle wrote:

I get "Service Required" when I start up but the car was fully serviced only in January this year and has done only about 8k miles since then. Given the uncertainty (there doesn't seem to be a reliable way of knowing if the oil is compromised) is it simply best just to get the oil changed or am I missing something.

Or should I just ignore the message?

Sods law in a good way - just ordered 10L of oil and a filter - message gone! Geoff

the message is probably still there , its just decided to keep it quiet for a while

Yep it came back!!! Geoff

I get the service required message on my SDV8 4.4 around every 3k miles since I retired and don't do many long journeys any more. The dealer said it was due to the lack of prolonged higher speeds over distance which I try to do if I can, as I don't want a DPF failure. I used to do 15k miles a year, now do around 5k. When they checked my oil it was at 8% saturation so had to be changed as over the recommended limit. I does seem stupid that now I do a 3rd of my old yearly mileage I now have to change the oil once or twice a year between services, all so an engine can meet emission regulations. True what they say though, I'm pretty sure my next car is going to be a petrol engine, but I don't want an SVR gas guzzler and as I like to buy my cars around a year old , I'll have to wait for a 2nd hand 4L petrol FFRR as they've only just come out. This will at least avoid the DPF, diesel in oil and not enough long runs scenarios relating to diesel engines. Steve

Main car : FFRR L405 Vogue SDV8
Other car : Vauxhall Lotus Carlton
Past cars : FFRR L322 Vogue TD6 SE (Sept 2006 MY07) ; LandCruiser SWB ; 4-Runner ; Supras; XJS V12 LeMans