I know this subject has been done to death, but as search isn't up yet I'll just have to ask one more time :-)

03 WRX is having its 10k service soon. One dealer has offered semi synthetic oil or fully synthetic oil for an extra £20.

Do i need fully synth? i don't really cane my car (too) much (well, i won't be attending any track days in it!).

cheers.

 

ScoobyClinic always recommend fully synthetic such as silkolene

 

Fully synth is better due to its abilities to handle the temps you get with turbochargers, it wont break down as easily either so does its job better and for longer than a semi synthetic does. The only thing id say is see what oil your dealer offers, if its the shell 5w30 then decline as its too thin, it needs to be in the 10w range or a 15w to be any good.

Tony

 

I was told by my dealer that they refuse to put fully synth in as its too thin.
Said somthing about it not offering adequate protection.

I did find it strange as I used to put nothing but fully synth in my Clio.

 

As a sweeping generalisation that's a load of sh*t. It's a bit like saying all women are tarts. It's not as though fully synthetic oils are only available in one weight, there's a wide range available.

Sure, some full synths are thinner than ideal, but some are just right, and will protect the engine better than any semi. Pick any one of Mobil 1 Motorsport 15w/50, Motul 300V 15w/50 or Castrol RS 10w/60 and you'll be fine.

 

Maybe you should ask yourself is 10k miles toooo long between oil changes for such a high performance engine. IMHO

Personally I to do mine every 5K with Fully Synthectic.

Tony

 

dealer told me they use 5w30 BP semi-synth. but make sure only fill half way up dip stick - apparently full sump can cause ignition/turo fault if oil vapour gets into dump value or somthing?

dont know how can say full synth is too thin, but then use 5w30 - semi or full, 5w30 must be like gnats ****!

 

...but they are though aren't they?

 

.use only fully when engine as done 12000mls or more

 

My 03 is running fully synthetic!

 

I use 100% synthese 300V competition MOTUL 15W 50 MOTOR OIL , never had no probs ?? cheers Alan,

 

i use 5w30 fully synth in my my93. the reason i use it is because of the american haynes manual for the legacy recomends it for the turbo enginres.
i've run on it for 2 years with out a problem, but i do change every 2k, the book recomends every 3k miles.
oh and i pay just £14 for my oil from a local company which blends oils.

 

I agree with greasemonkey, Pick any one of Mobil 1 Motorsport 15w/50, Motul 300V 15w/50 or Castrol RS 10w/60 and you'll be fine.
I use Mobil 1 Motorsport 15w/50, its always had it in, and changed every 5k, just got 5 litres from Halfords cost about £43

 

Provide your own oil and the fully synthetic will be cheaper than the dealer charges for 'natural' oil.

Castrol RS 10W/60 for me. £100 for 16l, which will do 3 changes. Delivery is quite quick.

 

i used motul 300V 15/50,never had any problems.