Diesel in sump

[boborob]

Does anyone know the capacity difference between the oil full mark and the x mark on the dipstick,so I can
suss out how much diesel I've got sloshing about in the sump?

[dunhill1984]

I hope you ment oil in the sump and not diesel--- that would be bad!

[Deeps]

Nope he means exactly that Mr Dunhill1984. The fact that diesel can get past the injectors (?) and into the sump thereby diluting the oil is the reasoning behind Mazda modifying the original dipsticks so that the newer items now have the 'X' mark as an indication of the maximum acceptable dilution of engine oil. When I first started driving diesel cars the engine oil was eaten up and regular checks of the dipstick were required. March forward a few years and instead of the fluid level creeping towards the lower end of the scale (min mark) it's now creeping up. This is all in the name of progress I hasten to add LOL.

[Anchorman]

It gets past the pistons during regeneration of the DPF.  This skyactive engine is one of a number of manufacturers that use post injection to super heat the DPF.  The post 2017 models virtually don’t do it through newer pistons and rings.

[dunhill1984]

well i learnt something today

[boborob]

Found out from Mazda that the capacity difference between the oil full and the x mark is 1.5 ltr,so even at halfway it would be 3/4 of a ltr,
 that'll do wonders for the oil viscosity. 

[sodit71]

boborob That is exactly the reason I have started changing my oil at 6000 mile intervals.  My wife and I tend to keep our main vehicle for 6 years plus and would rather pay for the oil change than fork out for other much more expensive stuff.  Must admit we have now come full circle as the Discovery we bought in 1993 was oil every 6000 the Honda CRV was every 12000 luckily we no longer do 15000 to 20000 miles per year.

[Nickg]

Having experienced the dreaded oil pressure light coming on due to poor quality oil I also want to start changing my oil at 6000 mile intervals. The car is now out of warranty so this something I can do myself.
The important  question is how do you tell the ecu that the oil has in fact been changed?
Is it simply by using the maintenance display or do dealers have a special ecu re-setter?
I seem to have read somewhere that the software that controls the DPF needs to be informed -- is this correct or am I reading too much into this oil change business?

Lots of questions and I hope some knowledgeable member can set me straight.

Thanks in advance.

Nick

[boborob]

to set the 2016 Mazda CX-5 maintenance light after an oil change, please follow these instructions:
1. Turn the ignition to run (do not start the engine).
2. Press the UP or DOWN part of the INFO switch to highlight the SETTINGS menu and press the INFO button to confirm.
3. Scroll to MAINTENANCE and press the INFO button to confirm.
4. Scroll to the item that needs to be reset (SCHEDULED, TIRE ROTATION, TIRE PRESSURE) and confirm with the INFO button.
5. Scroll to SET TIME or SET DISTANCE and confirm with the INFO button.
6.
turn the ignition off and then start the engine to verify the indicator has been reset.
hope this helps.

[Nickg]

boborob.    Thank you very much.  That's just what I needed to know. Either I or my friend ( a mechanic in a small local garage) will now change the oil and filter.  I have already researched the correct Total oil - with help from another useful post on this site.
I see no reason to feed the "stealer" for this service.

As a comment on your info about the amount of diesel in the oil to raise the level to the X mark.  Good god that's an aweful lot of dilution.  Shame on you Mazda.  This will be my last diesel car.  Shame really but there you go.

Cheers and thanks again.

Nick

[Jonno21]

boborob.    Thank you very much.  That's just what I needed to know. Either I or my friend ( a mechanic in a small local garage) will now change the oil and filter.  I have already researched the correct Total oil - with help from another useful post on this site.
I see no reason to feed the "stealer" for this service.

As a comment on your info about the amount of diesel in the oil to raise the level to the X mark.  Good god that's an aweful lot of dilution.  Shame on you Mazda.  This will be my last diesel car.  Shame really but there you go.

Cheers and thanks again.

Nick

Just for reference Anchorman has reported no oil level dilution on his 2017 plus CX5. Mazda appears to have fixed it for 2017's and later. I will monitor mine also. (Bought October 2018). Don't jump the gun just yet. By the way I do get better economy than my 2016 CX5. (39mpg for 2016 and 46mpg for 2018 as calculated by Fuelly on fill ups). Also does less regens now.

[Nickg]

Jonno21,
Thank you for the reply. I had read the reports you mention.  My wife and I like the car very much (it's actually her car - mine is an MX5......love it ).
As a car it drives pretty well and I reckon it occupies the "sweet spot" between a BMW X3 and say a Dacia Duster!!
The real problem is the DPF and how it is cleaned/maintained.
In an ideal world I would buy the same again but I would really want it to be electric and have say, a 200 mile range.
I could be be persuaded to go diesel but it would have to be ad blue and not excess fuel down the exhaust port to maintain the DPF.  The latest CX5 does this so it will be up to the salesman and his deal.  I don't hold out much hope but next year I will give it a shot.

Does anyone know which manufacturers use ad blue and which use the excess fuel method (post injection) to clean their DPF's?
 
Cheers    Nick

[ROCKETRON]

I think that most of the diesels on the market put diesel into the exhaust to heat up the dpf to burn off particulate matter. A small number of them actually inject the diesel into the exhaust manifold and so isn’t in the combustion chamber to dilute oil. The adblue that a lot of newer diesel are now using is for reducing oxides of nitrogen and has nothing to do with burning off particulates in the dpf, that still carries on as usual.
The filling up of the sump with diesel only happens when you are doing short runs and car keeps aborting regens. I only do long runs in my 13 reg ,although I don’t use it much and it has never had more than a mm or 2 on the dipstick between oil changes.

[Nickg]

Thank you for the good info.  The more I know the less I know!!!!
Off for a break now so I'll look further into this later on.

Nick

[Anchorman]

The latest CX5 uses Adblue.