Synthetic or fully synthetic oil?

[ismellburning]

Hello everyone and apologies for what might be the dullest thread in history.

My banger is due an oil change. In the spirit of bangernomics the most obvious thing to put in is semi-synthetic oil, but I've got an eye on the slightly longer game: will fully synthetic give me *that* much better economy, and a few more thousand miles from the engine?

All experiences/hints/tips etc appreciated, innit.

[Fire99]

Honestly? It does in part depend a little on the engine. Some engines (RX8 for instance) are quite specific about engine oil grade / quality.

For an old banger, a good quality semi-synthetic would be more than fine IMO with it being far more important to change the oil regularly rather than it being fully synthetic.

In a nutshell I'd say use decent 'semi' and but change it frequently.

[Vince70]

Oil technology has come such a long way that modern semi synthetic oil is most probably a lot better than the oil which was originally used on any old car.
If you doing 20000 miles between oil changes go for full synthetic if your only doing 6000 between changes then go for the semi.
I use semi synthetic in mine and do around 6000 miles a year I've never had a problem.

[ismellburning]

Semi synthetic it is I think. Always nice to get a recommendation that pleases the bank manager.

I change oil every 10k or one year. It's only a four hole 1.4 so I'm after economy and mechanical protection rather than a (presumably miniscule?) performance bump.

Cheers guys

[Alex]

Most "synthetic" oil is not truly synthetic, but has a mineral base.

http://www.opieoils.co.uk/pdfs/tech-articles/Bases...

[J4CKO]

I would just put in what is recommended, a Volvo 850 T5 is a banger but still needs full synthetic but converseley there is no point running a 150k mile Toyota Corolla on Mobil 1, as long as something like that gets an oil change it will most probably keep going and if it doesnt the oil grade wont be a factor in its demise.

[ismellburning]

J4CKO said:

I would just put in what is recommended.

If only the French made it that simple - manual recommends either synthetic or semi-synthetic, but stops short of suggesting one of the other

[Fire99]

I don't normally promote businesses but if you're concerned, drop a post on the sticky thread:

http://www.pistonheads.com/gassing/topic.asp?h=0&a...

Opie are very good with their oil advice.

[J4CKO]

ismellburning said:

J4CKO said:

I would just put in what is recommended.

If only the French made it that simple - manual recommends either synthetic or semi-synthetic, but stops short of suggesting one of the other

Halfors 10/40 Semi Synth, its on offer at the moment, will be fine for most uses, filter is usually a fiver, dont forget a sump washer and thats your oil done for under 20 quid.

[opieoilman]

If it's french and not the newest, a 5w-40 or 10w-40 full or semi synthetic is fine (just to make it more confusing). If you want to save a few quid, go for a 10w-40 semi, if you want to protect as best possible, go for the 5w-40 synthetic.

http://www.opieoils.co.uk/c-656-5w-40.aspx

Out of those, the best ones are the Fuchs/Silkolene Pro S, Millers CFS/CFS NT, Motul 300V, Redline and Gulf Competition. The Motul 8100 X-Cess, Millers XFS, Fuchs GT1 XTL/Supersyn, Gulf Formula G, Shell Helix and Mobil Super 3000 are good, cheaper alternatives.

http://www.opieoils.co.uk/c-657-10w-40.aspx

A cheaper 10w-40 will be fine and I would either go for the Fuchs Syn MC, Shell Helix, Millers XSS or Motul 6100.

Cheers

Tim

[ismellburning]

All good stuff, thanks very much for tips/words of wisdom etc. Look out for a "I've ballsed up my oil change" thread in the next few weeks.