Mineral Oil or Synthetic for E200, which is better?

[wuqi25]

I was wondering, for a '91 E200, should it be using mineral or synthetic engine oil? I just had an oil change and used synthetic instead of mineral as i wanted something better for the enginer. Which is better? Also, one of my friends who i spoke to told me that using lower grade unleaded 92 petrol could have caused the head gasket problem due to higher temperature. Is it really true?

 

[Myros]

92 octane

Synth is probably better, but if your engine is used to mineral, you shouldn't just change it and hope for the best. Click the link below and have a good read. 92 octane is a bit rare in the UK, we are stuck with 95 and 97. I wouldn't like to run an engine on 92 unless it were set up for it. It might even burn your pistons or your valves, as well as destroy your plugs. Stick to 95 or 97 if that's what the handbook tells you. Have a look at the petrol flap, it should say there which octane to use.
http://www.chris-longhurst.com/carbibles/engineoil_bible.html

 

[wuqi25]

Thanks a bunch, now i realise i should have stuck on to using mineral instead.

 

[tom7035]

Synthetic oil is the modern equivalent for base mineral oil and has far superior characteristics designed to look after your engine much better, quite apart from extending oilchange intervals. (I suppose if your engine is well worn it would be false economy, as it is expensive). It would be sensible also to flush the motor first before installing fully synthetic oil.

I doubt very much whether the oil used or fuel octane rating would have actually caused your blown head gasket, just coincidental.

As Myros says, the engine would have to be properly 'set up' to use 92 octane but avoid using it if you can.

 

[wuqi25]

Oic, thanks. Just checked, my radiator tank has chocolate mousse in it again

 

[tom7035]

DO IT Wuqi25, ASAP!!