But still why 50 when the engine recommends 20? 50 is going to be thicker than 20. 2ZR-FE runs on 0W20 all around the world, why are we different? Why is our manual different? There are hotter places in the world than Pakistan, there are colder places than Pakistan too.
Why is this ridiculous practice promoted by Toyota. The whole world is running 0w20 and 5w20/5w30 on 2ZR and only us run it on 5W50. Amazing.
50 means it actually is garha tail at high temperature (operating temperature of the car). 50 doesn't flow like 20, and 20 is what the engine needs.
Agreed. Always use the recommended oil, and to avoid bad practices, always cross reference Pakistani manual with other countries. Insist on the thinnest recommended oil in the manual, always. Go to consumer court if they threaten to end your warranty. Enough of these auto-looters industry.
Used ZIC 0w20 in Prius for 3 years, no issues at all. Car gives sometimes over 32kml in med-heavy traffic in summer with AC (for 1 trip, not overall).
Could be because Hyundai engine is designed differently, and it does need thicker oil in higher temps. You can try searching for a manual for the US, hotter areas, Nevada, New Mexico etc. This should confirm if this is the case. But please, 5w30 doesn't mean 5w50 or 20w50. Stick to what is written in the manual.