TD6 OIL SELECTION

[jx2mad]

If the oil in my td6 is changed every 10,000k, why should I use synthetic over mineral based oil?

[Homestar]

That's a good question, and I would love to hear an answer on this myself apart from 'That's what the factory recommends', but, at the end of the day, I stick to their recommendations. I have just posted a reply on the thread you have running there. I use QP lubricants oil in mine, and it is half the price of other synthetics, and meets the spec, and I am very happy with it.

This is the thread I started on that oil - http://www.aulro.com/afvb/l322-range-rover/149476-oil-rangie.html

Cheers - Gav

[jx2mad]

Where are all the experts? Surely this is not a difficult question!

[RangieBit]

Well I'm far from a tribologist but I suspect the simple answer would be that most synthetic oils are very broad in their spectrum of operating conditions. Whether that be high and low operating temperatures, their viscosity indices, or their ability to suspend soot and contaminants.

All of this is made even more complex with the latest rounds of engine emission specifications and engineering, and the requirement for diesel particulate filters. The soot characteristics are even more in focus as the wrong oil will kill a DPF very quickly.

Under most circumstances, I would think you would be very hard pressed to find a mineral, or even semi-syn which could match the specification that the manufacturers deem appropriate for their engine.

Since they designed and built the engine I suspect they would have a vested interest in attempting to ensure its longevity, and not simply the profits of the oil companies. Maintenance opportunities aside I don't think most people would be too complimentary of an engine (particularly a modern diesel) that didn't last at least half a million kilometers before wear and tear were noticeable.

Tolerances, and emissions are significantly tighter these days on diesels than those of yesteryear and this has meant that fluids (yes even the fuel) have had to adapt accordingly. Oil has to play its part in regulating the engine temperature, supplementary to the coollant system.

I also suspect it may be possible to achieve the same ends with a non-polymer (ester?), or mineral stock, but the cost might be even more prohibitive than the current range of synthetics to produce.

Them's my thoughts anyway.

Like Gav and Jim said indirectly, where are all our tribologists when you want one?

Cheers,
Iain

[bluegreygreen Rangie]

There is a guy on here somewhere that changes he's td6 oil every 20 thousand k;s and uses mineral oil... says he has done it for a while and engine runs fine (cant recall k;s on it)

The above freaks me out no end!, It is paramount to change turbo diesel oil often as you can and if you don’t use a good synthetic I would be changing your oil more often,

Me I’m fussy and I change every 5 thousand with filter and I use high quality synthetic oils... my Td6 has 311 thousand k's and runs like a dream, because i intend to keep the car for a long time I won’t sacrifice the oil changes, I’m sure it will do 600 thousand plus k's without missing a beat... why wouldn’t it
:D

In my old Nissan patrols that had low revving big pot 4.2 diesels I just used mineral oil and changed it every 5 thousand ks or less... that was fine but I think the TD6 engine works a little harder and is designed to rev higher under a fair amount of boost... it also has a cylinder head that no doubt works pretty hard been dohc and much finer tolerances etc so I think the better oil is the go and the reason bmw / rr recommend it

Generally high quality synthetic oil's retain their film strength better under extreme loads and in extreme conditions such as high temperature's etc so it is also worth remembering that a high quality synthetic will also continue protecting your engine where a lesser grade mineral may not which gives you extra security if something should go wrong and the engine has to run in extreme parameters such as overheating etc





Dave

[Waverley]

As Dave says it is important with a TD6 to change the oil at least every 10k because of the turbo but if wanting to keep the o'll girl going, every 5k is even better.

I was wondering if anyone was up around the 300k mark as I have less than 4k to go but Dave has already beaten me. I too intend to keep mine for the long haul.

Synthetic oils just maintain their viscosity integrity for much longer.

My thoughts.

Rob:)

[Homestar]

There is a thread running on Fullfatrr about high milage units, and there is someone on there that had over 300,000 MILES (480KKM) and still going strong, so they have plenty in them if well looked after

[rangietragic]

There is a thread running on Fullfatrr about high milage units, and there is someone on there that had over 300,000 MILES (480KKM) and still going strong, so they have plenty in them if well looked after Mine has over 200000 on the clock and i use Castrol Magnatec 5 w 40 [not magnatec diesel],i also use it on both my td5s.Seems to be ok.

[Daniel]

I've had my 2005 L322 td6 since new - now approaching 200k km.

I use ordinary off the supermarket shelf valvoline 15w - 40 turbo diesel engine oil and change it every 25k km. I change the oil filter every 2nd oil change.

I do however never drive the truck any less than 60 km after starting it and each trip involves low range off road work and then speeds over 120 kph for long sections.

I suspect that urban type driving is far more critical to an engine (especially with lazy auto transmission use than playing around with special oils and/or grades.