I was informed since it's considered a "luxury" car, I had to get the synthetic oil which costs much more than the regular oil.
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2001 Volvo S40 Question: How much is for oil change?
Answer #1Pvt-Public October 28, 2010, 13:44Master
Look in your owners manual and see if synthetic oil is either recommended or mandated. if it is not mandated use the recommended weight (ie. 5W-30 or what ever) regular mineral oil is recommended
Answer #2ZeeTech October 28, 2010, 17:34Master
Being luxury car or not has nothing to do with which oil is recommended.
On your car I strongly recommend to use synthetic because of different reasons, one of them is having a turbo, which runs extremely hot and uses the engine oil. Synthetic oils resist heath on a higher level - also flows and lubricates a lot better in cold temperatures. The other thing is, these engines are bad to build up sludge, clogs breather valves. Good synth. oils has additives to prevent sludge build-up.
Use good synthetic, like Mobil 1 and replace it at no more than 5000 miles if you want to save money on the long term, otherwise you will replace turbo, breather valve, de-sludge engine, etc...