Pug 205 GTi 1.6

Why does it matter what he used ?

You can freely mix different engine-oils if you want to top it up.

Infact, you can freely mix almost every fluid your car uses, with the obvious exception of the brake fluid.

Well not really, some of the non-synethetics won?t mix properly with synthetics. Not a huge problem but not ideal either.

It couldn?t hurt to change the oil anyway then as the old owner could well have used a bargain basement oil. Use a decent fully synthetic oil (obviously).

Streltsky

Careful here, the Pug/Citroen 1.9 doesn't like thin oils and a fully synthetic could start oil leaks from places you didn't know had oil. I'd go for a 10 or 15/40 semi synthetic, no thinner.

-- r

Where did you get that from ?

...if you want to waste your cash.

Fully Synthetic oil is used in more modern engines, to extend the service intervals (2 years / 20k) - quite simply, it lasts longer between changes. You have nothing to gain by putting it in a yearly-service 205 ! If he's going to service his 205 every year like he should, then there's no reason whatsoever to use anything other than branded semi-synthetic oil, in the grade stated in the handbook.

Agreed.

Well assuming the fully-synth was in the same grade (10 or 15/40) then it won't be any thinner than the semi-synth :) But as I've said, it's a waste of time. Engines are specifically designed to run on the oils specified in the handbook - you shouldn't ever deviate from these unless you have a very good reason.

Most older Pug engines seem to leak, I thought they were fairly famous for it. I use fully synthetic in my 1.8D and although it does leak it?s only small amounts, not even worth refilling. I?m not fussed about a bit of oil on my engine, which is good because it?s been a while since I cleaned it and it?s got a fairly good coat on it at the moment :) I?d have thought that the benefits of using fully synthetic oils outweigh having an oily engine, maybe it?s just me :?

Streltsky

I agree, but..... The more commonly available fully synths seem to be much thinner than the semis, I used a semi-synth in my BX16v as I live 3 minutes from a fast running dual carriageway and wanted the better cold running lubrication for the dash up to 60-70mph before the oil was up to temperature. Another point in these engines is to always use an oil filter with an anti-drain valve, the independent specialists always use the original Purflux filter as they are good and cheap as well... Try GSF.

Horses for courses.

-- R

But there aren't any benefits - fully-synth just lasts longer between changes.

There's no point using Fully Synth oil, unless A. You're leaving it in for

You can find a description like this on any of the major motor oil manufacturers websites

Among the many performance advantages that synthetic lubricants offer is their ability to remain stable at high temperatures (under which conventional oils can begin to breakdown) and remain fluid at very low temperatures (under which conventional oils begin to thicken). This provides optimum lubrication at extreme temperatures, reduces wear and tear, and makes for a cleaner, more efficient engine.

Plus other advantages

I will however retract what I said about mixing, according to the maufacturers all it does is "blend" the characteristics of the oils.

Streltsky

...temperatures which are infact higher than your engine will reach. If this wasn't the case, then your engine would require fully-synth oil :)

See what I'm getting at here ? If the features of fully synth were reuired for optimum operation of your engine, then that's what the manufacturer would specify - exactly like they do for the 210bhp V6 in my Coupe.

Do we get "very low" temperatures in the UK ?

Let me expalin my circumstances for choosing synth. I drive my car hard, therefore the engine will run at a higher temperature than it was built to. There is the fact that an engine will run slightly cooler with synthetics, plus I would be loosing the lighter fractions of a mineral oil at a higher rate than usual. Also I do lots of miles (15k in under 3 months recently) and I don?t always have the time and money to do an oil change when I need to. I use Castrol GTD, which is recommended for my engine (see castrol website). If I used a non-synthetic oil and drove the car the same way as I do now I would risk loosing the lighter fractions, especially if I didn?t have the time or money to change it, and therefore significantly increase the chances of causing engine wear. I used to use non or part synthetics but they were always slightly gritty when I changed the oil. It?s my personal choice. I understand why you chose non-synthetics but I?d rather not. Plus I know we don?t get cold weather, I?d just copied and pasted.

Streltsky