Change oil from Semi to Fully Synthetic

[Gilo]

Hi,

I've got a 2003 LC 1.8T at 40k miles.

It's always had VAG Semi-Synthetic oil at its VW or SEAT services. I'm doing the next oil/filter change and thought about changing from Semi to Fully Synthetic oil.

If I change to Fully Synthetic, is it safe for the engine after 40k miles with a Semi?

Are there any things I need to do during the change over (flush, etc)?

Or shall I just stick with Semi?

Cheers,

Gilo.

 

[Willie]

I'm running Millers fully synthetic with no problems. This was recommended by Seat indepedant garage that I used to use and many others on here use
I wouldn't do an engine flush with additives but thats your car and your own thoughts
I'm going to flush with new oil this time, seem to be a better way, if not the cheapest

 

[Gilo]

So, to change to Fully Synthetic oil after 40k miles of Semi, I simply drain out the Semi and refill with Fully Synth?

What are the risks?

Cheers Guys.

G.

 

[Leigh15]

semi synth to fully synth is fine as far as I know. It's going the other way that can cause problems I believe

 

[Gilo]

I've done some surfing on this topic.

Best search condition in Google was "switching to fully synthetic"

It also brought up this link to Mobil's website with lots of great questions answered by Mobil!


http://www.mobiloil.com/USA-English/MotorOil/Car_Care/AskMobil/Flushing_Engines_Prior_Synthetics.aspx


Basically Mobil:

- don't recommend flushing the engine in order to prepare engine for the switch from semi to fully synthetic unless the engine has been poorly maintained.

- state that modern fully synthetic oils are compatible with semi synthetic oils, so a straight switch (either way) is OK.

 

[D.K]

So whot brand of oil would you recomend for a 10 k oil change on a mapped LCR 225.

 

[Willie]

I'd suggest Millers, but only because this is what has been used in all VAG cars serviced in Star Performance including loads of big turbo cars, oh and RobDon uses it so it must be the best

 

[Jonny]

The Seat Specialist that services my car uses Quantum Synta Gold 5w40 fully synthetic.

I'm not familiar with the brand (always used Shell Helix, Castrol, Mobil 1 etc. in previous cars) but apparently it's recommended by VW.

 

[andyj]

Fuchs Fully Syth is available from GSF for about £18 for 4L