Type of Engine Oil

Yes.

Generally agreed, but check that the API / ACEA rating is at least as high as the rating in the handbook.

With older vehicles with some types of engine, there may be a bit more to it than that. Some of the better wear preventing additives ain't compatible with catalytic converters so are no longer commonly used. This mainly is a problem with push rod engines, where the tappet loading is higher than modern multi-valve OHC engines. So for some older engines a high zinc older spec oil may be the best.

Other than Amsoil marketing crap is there any evidence for this? Apart from anything else the loading on a pushrod engines tappets is normally lower than on an OHCs.

You can mix the two personally i wouldnt though

Plenty.

Be interesting why you think that. Ever compressed valve springs?

The OP didn't quote a year for his Pug but I'd have thought it was past that period. Pug Owners' groups sometimes good for stuff like this.

Go on then, I've not seen any evidence that any oil complying with a reasonable spec has higher cam wera, all the modern MB specifications require the opposite

Yes.

Thanks to all for responding to my post.

Someone asked about the year of my Pug. It is F reg (1989)

Someone else mentioned API/ACEA. I am not familiar with theses abbreviations, neither is the manual. The manual says: Multigrade engine oil viscosity SAE 10W/40 or 15W/40. Duckhams recommend Duckhams OXR Hypergrade or 10W/40 Motor oil.

I hope I can mix them since I have the Semi Synthetic Oil to add.

Best wishes.

I have just looked at the oil bottles API and ACEA are mentioned on both but there are no numerical values given

It's a 1980s car.

It's letters and numbers, not "a numerical value".

I think 1989 could be old enough for Dave Plowman's points about anti-wear additives to be applicable (I would bow to his wisdom).

I am *very* surprised that the car handbook does not quote specific API / ACEA grades. The link I gave earlier suggests that oil suppliers whose bottles which are vague rather than specific may not be "reputable". Since it is a GTI (i.e. more collectable) I would suggest it is worth checking the PUG owners forums. You need to watch out for somewhat extreme petrol-head views (brand X is the *only* thing which works) but you also find genuine experts like our Mr Plowman and MrC. (My experience is in industrial rather than motor lubricants).

So it's designed to run with API SF but everybody used SG or better for the anti sludging spec. You'll have to try quite hard to buy anything less than SM spec though.

Modern engines are invariably multi valve OHC types. The loading at the actual cam is therefore very much lower. Pushrod engines have heavier tappets, pushrods, (single) valves. All that weight and inertia requires stronger springs and therefore much higher loading at the tappet/cam face.

Well, you'll have noticed that the springs on a multi-valve type are much easier to compress than pushrod ones, on a similar sized engine.

An 8 valve OHC, then? I'd ask about the best oil on the Club forum, etc. It may be it is happy with modern oils.

I'm not actually certain if the 205 GTI needs special consideration as regards camshaft wear. Just wanted to make it clear that the latest spec oil may not be the best choice for every vehicle. The major oil makers certainly ain't going to tell you that. ;-)

Which would be fine if it was true but in general they don't have lighter springs or lower loadings. The extra weight & lack of stiffness is what limits your revs & why they're outmoded, not the increased tappet wear.

Not particularly & they've often got smaller cam lobes with more agressive timings. Not that it's relevant as the wear standards have got tighter for modern oils not slacker.

The vast majority of engines in daily use by the average driver never get anywhere close to their rev limit.

I'm not attempting to defend pushrod designs. Although the lack of a cam belt might make them remembered by some with affection.

All I will say is it's well enough documented that modern oils will cause very premature cam wear on some pushrod engines. Don't really care if you believe this or not. ;-)

Which doesn't alter the fact that a Honda VTEC's got stiffer springs & higher loads than a Rover V8 and both of them will go near the rev limiit iif you floor an automatic gearbox.

That's my point, it's not well documented, there's a vast array of documentation that modern oils have better wear characteristics (even to the extent of specifically testing wear on an old style pushrod & tappet engine) and then there's some people on the internet who are upset that the only ep additive they know the name of isn't in there much anymore.