[Corollario]

Hello everyone,

I am new in this forum but decided to join after reading some threads. I live in San José, Costa Rica, were the climate year round is during the day between 22 to 33 degrees Celcius (71.6 F to 91.4 F) and in the night from 18 to 23 degrees Celcius (64.4 F to 73.4 F). I have a Toyota Corolla 1999 Japanese Version, with the second gen 4AFE engine and chasis code AE111. The car has 216,000 km or 135,000 miles on the clock. I have been the second owner and before it was mine it belonged to my Mom who gave it to me with 37,000 kms or 23,125 miles. I lived with my Mom when she had the car from the Official Toyota Dealer. She took the car to the Toyota Dealer's shop for oil changes. After I got it I sort of did the same and alternating taking it to Lube Centers. Almost always have use Toyota Genuine Oil filters with exeption of some Luberfiners filters a few times. Now I have also almost always used conventional mineral 20w50 oil in the changes, as I last remember checking in the lost by me, Toyoya Handbook, it says if I am not mistaking, to use 20w50 for the climate's temperature range where I live. But I don't remember seing anything about mineral or synthetic. Now I am wondering what could be the best oil I could use for my car. I have never had any oil leaking issues or high burning comsuption oil that I I can remember. Withing a 5,000 km or 3,000 miles interval, I can almost asure that at the end of the change the oil check stick stays the same at FULL. So having this said, since some how my 135,000 miles car is not having any leaking or oil comsumption issues, should I start using a Fully sinthetic 20w50 oil like Red Line 20w50 or Amsoil 20w50 which have exelent ratings or should I stick with my regular Castrol 20w50 oil ? I read in this forum a thread by a user saying that ''4AFE engine don't like fully synthetic oil, that he had to find out the hard way''. The reason I would like your thoughts about this, is because if 20w50 synthetic will work just fine in my engine, then maybe synthetic oil could provide me with better wear and friction protection because I plan on keeping the car for long. Now honestly I don't know if its the mechanics here or dealer reps. but whenever I asked them stuff like this, they seem to give me more their opinion than something based on research and testing. So if full synthetic oil is not the best for my engine, I was planing on using Castrol GTX or Castrol GTX High Mileage ( High mileage I considered it for a higher level of ZDDP content), since these two oils have really good feedback from opinions of people that have used it. Also if I find out that full synthetic is not the best for my engine, I will lean also to Castrol conventional oil, since it is the one that I have used the most so far and with great results.

Thanks a lot for reading my post and hope I get the most replies !!

[7afe]

im going to use to Castrol GTX (15w-40)as its cheaper but find it strange to hear using synthetic is bad