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Hi.
I bought a second hand car. It has 56, 000 Km mileage. I just changed the oil with full synthetic Repsol 5W-50 (Carrera) viscosity. I researched on the internet that it's too thick and will cause issues (leaks, etc). I live in South East Asia, tropical climate (28 to 34 degrees Celsius). I drive around 10-12 Km a day with heavy traffic during daytime but I go home at night (no traffic). I went to the mechanic who replaced the oil and told me that it's ok. I'm starting to doubt now based on what I read.
The previous owner changed mobile phone number I think because his number couldn't be contacted anymore. He did mention before that he only used fully synthetic oil. Car is in good condition when I bought it. I'm worried now. Should I just replace it with lower viscosity ASAP? In the manual, I found 10W-40, 10W-50, 15W-50. There are lower viscosity too like 10W-30 in the manual. Is changing to lower viscosity after few days of using higher viscosity bad? Or should I just wait for 5 more months and change the oil with 10W-40?
I used Repsol 5W-50 because it's the only oil that I found in the mechanic shop with API-SM. The rest that are 10W-40 and 5W-30 are API-SN. I read that API-SN is compatible with old cars. Is this true as well?

Thanks.
 

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Demon Spawn
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yes that's far too thick. change it, and yes synthetic blend is fine, I wouldn't use high mileage designated oil as it has seal sweller stuff in it that can actually be more harmful than good especially if you use it a lot then quit it can make the seals then shrink and leak more. changing back and forth from a blend to synthetic to normal etc and going with synthetic this time and a blend next and a regular after then a blend then synthetic etc is also not going to hurt anything just change the filter when you do so you don't mix different kinds in the filter and the filter should be changed at every oil change anyhow theyre cheap and are cheap insurance. main thing to do is check that you use a small amount of oil on the filter seal before putting it on, make sure the old filter seal comes off before the new filter goes on (double seals can be catastrophic) don't over tighten the filter hand tight and 1/4 turn or so is usually all that is needed don't over tighten or use power tools to take off or put on the drain plug and use the correct weight each time as well as a reputable brand of oil and filter
 

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You should be using 0W-20 synthetic oil.
CK
 

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Demon Spawn
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You should be using 0W-20 synthetic oil.
CK
depends on motor and region, in usa and Canada with the n/a motors 0w20 is recommended 5w20 can be used but many other markets such as mexico and Australia and some Europe markets use 5w30 and all turbo models use 5w30
 

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the first number is the viscosity at startup(cold engine) , the second number is viscosity at operating temperature. The first number can be 0 or 5 or 10 depending on the climate were you leave. The second number - never use anything higher then 30.
 

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Hi.
I live in South East Asia, tropical climate (28 to 34 degrees Celsius or 82F-93F ). I drive around 10-12 Km a day with heavy traffic during daytime but I go home at night (no traffic).
Thanks.
This is IMPORTANT information regarding your question.

oil_chart.jpg

The hardest thing on auto forums is getting advise from the common sense perspective. There is lots of Empirical Data and information regarding your question.
 

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Hi.
I bought a second hand car. It has 56, 000 Km mileage. I just changed the oil with full synthetic Repsol 5W-50 (Carrera) viscosity. I researched on the internet that it's too thick and will cause issues (leaks, etc). I live in South East Asia, tropical climate (28 to 34 degrees Celsius). I drive around 10-12 Km a day with heavy traffic during daytime but I go home at night (no traffic). I went to the mechanic who replaced the oil and told me that it's ok. I'm starting to doubt now based on what I read.
The previous owner changed mobile phone number I think because his number couldn't be contacted anymore. He did mention before that he only used fully synthetic oil. Car is in good condition when I bought it. I'm worried now. Should I just replace it with lower viscosity ASAP? In the manual, I found 10W-40, 10W-50, 15W-50. There are lower viscosity too like 10W-30 in the manual. Is changing to lower viscosity after few days of using higher viscosity bad? Or should I just wait for 5 more months and change the oil with 10W-40?
I used Repsol 5W-50 because it's the only oil that I found in the mechanic shop with API-SM. The rest that are 10W-40 and 5W-30 are API-SN. I read that API-SN is compatible with old cars. Is this true as well?

Thanks.
Just wait until your next oil change. You're okay with the 5w-xx for startup. The 50w in normal operation at your temps should not be a problem.

Follow what your owner's manual says. It probably says 5w30 or 0w20. Either would be fine, but the 0w20 will provide a little bit better fuel economy.

Ralph
 
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