hi

just read some of the huge oil debate, had an oil question buthought best to make new thread and play safe lol

anyways

sister has a 55 punto

oil is at minimum she neds to top it up. she has hardly any money so cant afford oil filter change. problem is she off on holiday at weekend and we are not entirely sure what the oil in the car is. am pretty sure its either mineral or semi symphetic. as she had a mechanic do a cheapish filter oil chang as part of last years mot.


ssooo what is it best to top up with mineral ? or semi symphetic, bearing in mind it could have either in it?

also i have my own bottle of selenia 20k for me sporting is it ok to use that in hers ya think ?


thanks in advance to all you superb experts

Lend her a few quid, tesco branded oil is less than a fiver for 5 litres and a filter is cheap as chips. If it hasn't been done for a year/6k miles etc. it would really be advisable.

was done about 8 months ago so it is due really,

just out of curiosity what is selenia 20k is semi or full sythetic?

It's synthetic-based oil....this is when the issue gets yet more complicated! I think basically that means it's not genuine synthetic oil in terms of it being processed at a molecular level but it has been fiddled with. I wish I knew more about it.

But I think it's overkill for a punto if she hasn't much money. Seriously, oil that's more than good enough for that engine is a few quid in tesco and a oil filter isn't too costly!

cheers again. synthetic based dam dint know that one existed liek u wish i new mroe about oil.

my dad swears by 20w50 £5 a gallon for his uno. its a wreck of car but dam thing keeps on going so he must be doing somethng right.

Any clean oil is better than old oil that hasn't been changed for years...
Like said, get some supermarket stuff or Castrol Multigrade or whatever it's called...filters are about £6...

If you're desperate, just top up with any old toss and avoid thrashing the engine. But as soon as poss, do a full filter and oil change using something decent like Castrol GTX (only about £12 for 5 litres).

The Negotiator said:

It's synthetic-based oil....this is when the issue gets yet more complicated! I think basically that means it's not genuine synthetic oil in terms of it being processed at a molecular level but it has been fiddled with. I wish I knew more about it.

But I think it's overkill for a punto if she hasn't much money. Seriously, oil that's more than good enough for that engine is a few quid in tesco and a oil filter isn't too costly!

Click to expand...

is it a hypo on crack oil?

whoops i mean hydro cracked?

Hydrocracked oil contains modified mineral oil basestocks, no proper synthetics.

Your sisters car would be fine with a 10w-40 semi-synthetic.

Cheers

Oilman, if you're around, is this the difference between "synthetic based" and synthetic? (that it contains modified mineral oil base stocks rather than actual synthetic?) If so, when it's true synthetic, what's the raw material?

The Negotiator said:

Oilman, if you're around, is this the difference between "synthetic based" and synthetic? (that it contains modified mineral oil base stocks rather than actual synthetic?) If so, when it's true synthetic, what's the raw material?

Click to expand...

Indeed, "synthetic blend", "semi-synthetic", "part-synthetic" etc are petroleum oils blending groups I, II and III, no IV or V.

IV is PAO (Poly alpha Olefin)
V is Esters

Basestock categories and descriptions

All oils are comprised of basestocks and additives. Basestocks make up the majority of the finished product and represent between 75-95%.

Not all basestocks are derived from petroleum, in fact the better quality ones are synthetics made in laboratories by chemists specifically designed for the application for which they are intended.

Basestocks are classified in 5 Groups as follows:

Group I

These are derived from petroleum and are the least refined. These are used in a small amount of automotive oils where the applications are not demanding.

Group II

These are derived from petroleum and are mainly used in mineral automotive oils. Their performance is acceptable with regards to wear, thermal stability and oxidation stability but not so good at lower temperatures.

Group III

These are derived from petroleum but are the most refined of the mineral oil basestocks. They are not chemically engineered like synthetics but offer the highest level of performance of all the petroleum basestocks. They are also known as “hydrocracked” or “molecularly modified” basestocks.
They are usually labelled/marketed as synthetic or semi-synthetic oils and make up a very high percentage of the oils retailed today.

Group IV

These are polyalphaolefins known as PAO and are chemically manufactured rather than being dug out of the ground. These basestocks have excellent stability in both hot and cold temperatures and give superior protection due to their uniform molecules.

Group V

These special basestocks are also chemically engineered but are not PAO.
The main types used in automotive oils are diesters and polyolesters. Like the group IV basestocks they have uniform molecules and give superior performance and protection over petroleum basestocks. These special stocks are used in all aviation engines due to their stability and durability. Esters are also polar (electro statically attracted to metal surfaces) which has great benefits. They are usually blended with Group IV stocks rather than being used exclusively.

It is common practice for oil companies to blend different basestocks to achieve a certain specification, performance or cost. The blending of group IV and V produces lubricants with the best overall performance which cannot be matched by any of the petroleum basestock groups.

Cheers
Simon

Thanks Simon, I got that from your other thread - hadn't seen your post before I asked.

an oil filter will cost you between £1.76+VAT (so £2) and £5 (inc VAT)
The cheapest I find are Coopers, which are also incidently much better quality than other ones.
And some Cheapo 10w40 semi syn will do, can get some from £5 from morrisons and tesco value ranges, does the job.
You can change oil, oil filter, air filter and plugs for £15 on these cars thats inc VAT too. And a bottle of unbranded engine flush will cost about £1.50 from any parts dealer. Worth doing.