so if the engine didnt fail in 50K miles it's ok even with sunflower oil..... no worries, it will fail in the next 50\k being bastardised like that....i hope i'm wrong and then i'll apologise.... we'll speak again after that, you can just keep humiliating your engine with the wrong spec oil though... each for it's own o_O:rolleyes:

I doubt if it will make any difference, so long as you change the oil often enough. Synth will run longer than mineral. Obviously, it is a good idea to use diesel oil in a diesel, and to use a viscosity grade appropriate to the climate where you are.

Personally I would not put any mineral oil into a turbo'd engine whether its petrol or diesel.
My preference in turbo engines is a full synthetic. A turbocharger doesn't have any bearings on the turbine shaft,
it relies on a film of oil to lubricate and prevent wear. Any breakdown in the lubricating oil will cause rapid wear on the turbine housing, this will then allow more oil to escape through the turbo and allow the turbine to move around excessively. The turbo is very hostile environment for oil to work, very very hot and very high speeds - several tens of thousands of RPM. The heat alone can cause lower quality oils to break down and also 'burn' or 'cook' the oil, when this happens you can get tiny lumps of carbon in the oil.
The better the quality of oil the longer your turbo is likely to last.
Many folks can remember the Fords etc. of the 1980's with rattling hydraulic tappets. this was down to the carbonising up
of the tappets due to mineral oil 'sludging'. Good quality full synthetic oils is why we don't have this problem now.
So imagine that sludge staring to build up in your turbocharger.

I have a 60 year old Standard 10, I put mineral oil in that. Everything else has full synthetic oil in it.

I would not recommend synth oil for very old turbo engines like a 2.5TD. Probably glaze the bores and leak all over the place.
 
:D:D

I think I bought some of the last Castrol stock of A1 from Asda of all places and wondered wtf was going on with the spec until I found out A5 was the new top dog.

I always find what I have in the shed is the best! ;) And the cheapest! :)
 
I would not recommend synth oil for very old turbo engines like a 2.5TD. Probably glaze the bores and leak all over the place.
IMO it's not about the age of the engine but about being turbocharged cos mineral or semi oils suffer by thermal breakdown in the turbocharger and loosing theyr lubricating quality in no time while synthetic oils are more resistant to that, for somebody who is not monitoring the EGT it's risky to put mineral oil in the engine cos if it runs on high EGT without knowing it that oil is broken after less than 2K miles, i have a lubrichek oil tester and checked many oils on friend's D2's and defenders and found semi synth oil which hit the end of scale and the oil was changed less than 3K miles before... i'm changing my oil based on that not on mileage and the fully synth PD oil was still good after 5K miles though i changed it anyway
 
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IMO it's not about the age of the engine but about being turbocharged cos mineral or semi oils suffer by thermal breakdown in the turbocharger and loosing theyr lubricating quality in no time while synthetic oils are more resistant to that, for somebody who is not monitoring the EGT it's risky to put mineral oil in the engine cos if it runs on high EGT without knowing it that oil is broken after less than 2K miles, i have a lubrichek oil tester and checked many oils on friend's D2's and defenders and found semi synth oil which hit the end of scale and the oil was changed less than 3K miles before... i'm changing my oil based on that not on mileage and the fully synth PD oil was still good after 5K miles

Sure that is all quite accurate, and if it is working for you, keep doing it.:)

I don't have much to do with turbocharged engines, and I do use synthetic oil in my Mondeo.

But it is also a fact that I ran my 2.5 TD Ninety for 8 years, and over 30k miles, mainly off road and farm work, on multigrade mineral oil. No issues.
On that sort of usage, I doubt if the Turbocharger spools up that much, it is just turning over slowly. Horses for courses.
Multigrade mineral is specified for a 2.5 TD by the manufacturor. Synth oil barely existed when those where built.
 
IMO it's not about the age of the engine but about being turbocharged cos mineral or semi oils suffer by thermal breakdown in the turbocharger and loosing theyr lubricating quality in no time while synthetic oils are more resistant to that, for somebody who is not monitoring the EGT it's risky to put mineral oil in the engine cos if it runs on high EGT without knowing it that oil is broken after less than 2K miles, i have a lubrichek oil tester and checked many oils on friend's D2's and defenders and found semi synth oil which hit the end of scale and the oil was changed less than 3K miles before... i'm changing my oil based on that not on mileage and the fully synth PD oil was still good after 5K miles though i changed it anyway
Do you really think your oil testing ability is better than say Shell or any of the other major players in the oil game, because on there bottles of semi-synthetic it says amongst other things ideal for use in turbo charged engines, because that would mean there lying to everyone and they dont test there stuff before putting it on the market, which I would imagine would leave them open to many a lawsuit.
Also in the book that came with my td5 there is no mention of using PD oils or fully synthetics
 
Multigrade mineral is specified for a 2.5 TD by the manufacturor. Synth oil barely existed when those where built.
then it would have been quite hard to recommend an inexistent synthetic oil :) ... the oil industry had a huge evolution since then so if better oils came to the market should we stay with the old ones ? .... it's the same like in other systems, if something better was invented i'll use that not stick to the old stuff, for example i wish i could find this https://hychill.com.au/products/minus-30 locally cos i'd deffinitely put it in mine

johnlad said:
....
Also in the book that came with my td5 there is no mention of using PD oils or fully synthetics
......nor it is to remove the EGR or remap it ....also there are tyre dimensions recommended in the book too :)

i'm not gonna argue on that, as i said, each to his own
 
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then it would have been quite hard to recommend an inexistent synthetic oil :) ... the oil industry had a huge evolution since then so if better oils came to the market should we stay with the old ones ? .... it's the same like in other systems, if something better was invented i'll use that not stick to the old stuff, for example i wish i could find this https://hychill.com.au/products/minus-30 locally cos i deffinitely put it in mine

I always stay with what it says in the book. And I also usually avoid threads about oil! ;):)
 
Do you really think your oil testing ability is better than say Shell or any of the other major players in the oil game, because on there bottles of semi-synthetic it says amongst other things ideal for use in turbo charged engines, because that would mean there lying to everyone and they dont test there stuff before putting it on the market, which I would imagine would leave them open to many a lawsuit.
Also in the book that came with my td5 there is no mention of using PD oils or fully synthetics
Come on, his statement is based on his own personal experience and not official methods :D
 
Sludging isnt going to be an issue these days as the oils are much better at keeping the internals clean.
i take off plenty of rocker covers and sumps at work and you just dont see sludge at all.

I agree, sludging isn't much of an issue these days - because almost all oils you buy will be at least a semi synth. I was making the point that I would not put a mineral oil into any engine with a turbocharger, and using the sludging as an example of what happens to a mineral oil as it degrades.
 
Do you really think your oil testing ability is better than say Shell or any of the other major players in the oil game, because on there bottles of semi-synthetic it says amongst other things ideal for use in turbo charged engines, because that would mean there lying to everyone and they dont test there stuff before putting it on the market, which I would imagine would leave them open to many a lawsuit.
Also in the book that came with my td5 there is no mention of using PD oils or fully synthetics

There are different qualities of oil available, whether they are semi or fully synthetic.
Yes they will be suitable for use in turbo charged diesel engines if it says so on the tin. What it doesn't say on the tin is how long they will continue to meet that specification. I came across a situation a few years ago where an oil, supplied and branded by a major (USA owned) motor manufacturer, and sold through their dealership network, met the required semi synthetic specifications that they required for their own engines. But when tested having been used in their own engines for just a couple of thousand miles or so then failed to meet those same specs. Whereas a higher quality semi synthetic oil still met the specs. That is the difference between a good quality oil and a cheap oil, whether its a semi or full synthetic.

sierrafery likes to use a PD spec oil, the VW TDi engine is very demanding of its oil due to the mechanical pressures required to operate the injectors. So the PD oil specified for that engine is of a very high standard. So when he tests the oil in his engine oil he finds it staying better for longer.

I've not got a problem with folks using a cheaper oil, or a top quality oil. You pays your money and you takes your choice. But do be aware that not all oils are the same. Oils do degrade at different rates according to their quality. Better quality oils do cost more to blend.
 
I agree, sludging isn't much of an issue these days - because almost all oils you buy will be at least a semi synth. I was making the point that I would not put a mineral oil into any engine with a turbocharger, and using the sludging as an example of what happens to a mineral oil as it degrades.
only if it was left in too long and wasnt a higher detergent oil, lr never used a high enough detergent oil, when we used to strip farmers tds they were allways clean,you still see sludge if oils been left in far too long
 
I agree, sludging isn't much of an issue these days - because almost all oils you buy will be at least a semi synth. I was making the point that I would not put a mineral oil into any engine with a turbocharger, and using the sludging as an example of what happens to a mineral oil as it degrades.


Sadly at work we run some scanias and I hate scanias with a passion, out of date hard to work on bits of ****e!
But what they do have is oil spinner which we have to strip and clean each oil change which on the current Euro6 models is every 60k and the spinner may and I mean may have 1 or 2mm of sludge on the inside walls of the canister, now many moons ago same engine but previous shape model Euro2/3 engines the spinner would literally be half an inch thick with sludge and that was with oil changes at 40k, obviously engines have tighter tolerances but most of it has to be down to the oils of today.
We were tying the latest fuel saving syn oils back then but the older high mileage truck engines would either leak like a sieve, drink like a fish or blow up and sometimes all three at the same time, we went back to the old oil asap and the problems went away.
 
I have seen this kind of discussion many times, and commented before, turbochargers push lubricants to the limit, with high temperatures, and rotation speeds, synthetic oil is one of those luxuries that is well worth investing in. There will always be people who have run them on mineral oil and done fine for many years but its one area I don't cut back on, and many fully synth oils are quite cheap these days I use Halfords oil made by Comma, and change it regularly.
I can remember cars my dad ran that were absolutely clapped out at 60 to 80 K miles and had probably been de coked during that time, you hear of TD5 engines with 300 K on them still working, I think modern oils are part of that success story.
 
I dont think A1 exists anymore its now A5 which is totally logical!
You should see that I was merely quoting from the Disco 2 Owner's Handbook. I did qualify the statement be heading it with "This is from the Discovery 2 Owner's Handbook:-".
I claim no responsibility either way for the information gleaned from the quoted source.
If the specifications for the oils have been updated, I'll gladly defer to those who might know better, I just say to my garage "Fix it" closely followed by an "Ouch" when I see the bill.
If push comes to shove, I'd reckon that one of the "secrets" is to change the oil, immaterial of what type, kind or spec on a regular basis. Don't leave it in the sump until it reverts to its previous natural state.
 
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