Club 80-90 Forums

Hi
Just been to my local Asda pick up 2x 4leters of Castrol semi-synthetic 10w-40 £10 each
Nik

Take it back, you need Mineral oil for a T25.

^^^ Like Ian says and especially if its air cooled, will go through it like pi55

and its cheaper in wilko's

I think the replies are a bit over critical.
Castrol recommend Magnatec 10W40 for watercooled boxers, the wiki here recommends 15W40 by Quantum. The wiki also has some positive things to say about synthetics.
See https://club8090.co.uk/wiki/Al ... ecommended

If your van is Aircooled then wiki says 15/50 or 20/50 is right. Mineral 20/50 is £6 a gallon from Asda, £7 from Wilko, or £18 from Halfrauds, but it comes in a classier can.

From my experience with motorcycles, I can confirm that synthetic oil will weep from a worn seal when mineral doesn't.
However I've been using fully and semi-synthetic oils in my van for years. Specifically it had mineral oil from new until 1991, at about 35000 miles, when my VAG dealer did a service and charged me for vy expensive synthetic oil. When I queried this the 'service manager' said it was a VW recommendation - I asked VAG head office in UK to confirm but got no sensible reply. Since then I have used either 5W40 fully synth or 10W40 semi. It's now at 140,000 miles, no leaks and no oil usage between changes. I change at 5000 miles or annually, except for a few low mileage years where it went two years between changes.

jp

jpennington wrote: I think the replies are a bit over critical.

I prefer to call it honesty. You may of course choose to ignore our advice ... which is based on just under 7 year's experience of wbxers in my case and quite a few more in Ian's case.

Ian

I have used both semi synthetic and mineral oil in my van and i found that when hot the semi synthetic oil ran at lower pressures and had a tendancy to set the BOD off. Since switching back to mineral 15/40 no problems .

Mark

But you are talking about aircool and wbx engines.What about diesel engined T25s i only use semi synthetic for the 1Y engine fitted.

semi snythetic will literally fall out of an Aircooled!!!

its nowhere near the right oil