Mineral or synthetic oil

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Spailpin Fanach
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Mineral or synthetic oil

Post by Spailpin Fanach »

Hi all

I'm stocking up on engine oil in preparation for an oil change and to have a few litres to spare. 

I read somewhere that only mineral oil should be used, and not synthetic. I was thinking of THIS oil but unsure. It says "mineral" in title but "multigrade" on photo. Halfords describe the same oil as "fully synthetic". Bit baffled. 
1989 LHD VW T3/Type25 1.6TD JX Westfalia California poptop, 5-speed. 


There are two types of people in this world:
1. Those who can extrapolate from incomplete data

TONYT25T25
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Re: Mineral or synthetic oil

Post by TONYT25T25 »

I have stuck to Mineral oil for every change, lots of chat on here about oils, some say non mineral damages the oil seals others say it does not, I thinks it is a bit like coolant, don't mix and stick to the same type on change.
1984 Campervan 1.9DG Petrol WBX

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ZsZ
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Re: Mineral or synthetic oil

Post by ZsZ »

Synthetic oils are usually thinner that the engine needs. This is where the rumour is from.
If the viscosity and standard meets with the OE requirements then you can use whatever you can get.
Zoltan
1986 Multivan ex-Caravelle. Van since 2006, running mTDi 1Z since 2008 with Fiat Croma 1.9 TDid pump 2008-2019, custom pump since 2019
5spd custom box 4.57 diff + 0.74 5th

Dueller
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Re: Mineral or synthetic oil

Post by Dueller »

I rarely comment on the great oil debates in VW's but here goes my recent experience...

Rebuilt my DG and after a bit of thought and research tried semi synthetic 15x40, ran fine for a bit then at idle the light would flicker now and again, dropped it out after 3 days and 50 miles!

Changed to Comma 20w50 Mineral and all is fine, never saw that light again, all my air-cooled builds i use this in too, i only sell turnkey engines these days so have had a lot of practical personal experience, not just from twice yearly changes

As part of my rebuild i fitted a new oil pump (as well as water pump and fuel pump!) and cover but will confess i haven't ran it on my oil  pressure gauge to see what its doing, usually 2 bar at 80 degrees IIRC.

Due another change soon as i run it in more so will probably test it then

Personally im an old hand at skepticism on oils (and everything else VW) and the stories we read, I mean as if manufacturers don't know how to make stuff and the internet does..?



 
1989 Crewcab 1600TD JX - Gone to Romania
1989 Caravelle 1.9 AutoBox

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