hey guys do any one knows what kind of  engine oil should i use in my 4 valve car.  i went to buy engine oil but am found like 5W-30, 5W-40, 10W-20, 10W-30, 10W-40 and many more.  Do any one know what are those types for. and how much  quantity of oil should we use , as far as i know , 4 quart goes in 4 valve engine. 
anyone who have any good idea are appreciated to give some suggestion.

 first off what kind of car? if you check the oil cap in the engine its stated there. Or a simple google search with car make and model works too. and dont forget to change the filter too.

R u going to change oil yourselves?
Whatever weight of oil is recommended for your car, use that (Oil type printed on your engine cap). I own a 2006 accord and I use full synthetic oil and change oil every 5000 miles although they say I can go 7500. I could also use standard mineral oil which is a lot cheaper but performance wise, it's no good in the long run. There is also half-synthetic blend.

5w-20 is just the weight of oil for your engine type. Among that, you will find mineral oil(standard & cheap), half synthetic, and fully synthetic (much expensive, $60 for oil change they charge, and it is reasonable).

To be in the safe side, refer to your owner's manual for the type of oil and quantity.  Adding more oil than recommended can blow up your engine head gasket which can cost you lots of money.

Well nornally for cars with low mileage 5-30W should work..if you are talking about car with high mileage with worn out pistons and oil rings then 10-30W will work as it is more viscous at the higher temperature end..It is for regular cars,..if u are talking about high performance sports cars or the ones with diesel engine then it could be different,, It does not matter how many valves do you have in your car.. I am not sure there is any car with 4 valves..for a 4 cylinder car there has to be atleast 8,,4 intake and 4 exhausts

Good luck and have fun

Suggest to watch you-tube first , and have all necessary tools handy.

Never ever get underneath the car without proper jack up , you need ramp not the regular jack up tools to change wheels. Most car are esay but not all car.  Lack of proper tools most of the time simple work turn to a hard work.

Even in the ramp , make sure your car rear wheels are locked propery ( buy wheel locker too)  and shake the car to check for proper stationed. To learn you have to try it, but SAFTY should not be compromised.

Good luck. Please Share you exprience.

 hey guys thanks for the suggestions and in this case i am not trying to change my engine oil. actually its been like a 3 weeks i haven't drove my car and somehow i went to check the oil level and its was in low.  and i have drove 800 miles since i have change the oil, so i thought its not safe to drive a car with low engine oil so i thought to add some engine oil and i was confuse what kind of oil goes in engine. 
anyway guys i like the good suggestions
ani thanks chandrika, for letting me know abt the safety.

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