Background: this Elantra was originally owned by another friend of mine. I have maintained this Elantra since the 25K mark. Until this oil change, it was receiving oil changes with Quaker State Ultimate Durability 5W20 or Pennzoil Platinum 5W20 at 7.5K-10K intervals and genuine Hyundai oil filters.
Earlier this year, the Elantra changed ownership to a good friend of mine (the original owner moved out of state and no longer needed the car) and it looks like I will continue to maintain this car for the forseeable future.
This oil was in service for about 3 months. The engine air filter was a Mahle/Clevite with 20K miles on it, and the oil filter used was a Genuine Hyundai.
When this oil was placed into service at 78,994 miles, the ECM was also flash-reprogrammed to the latest calibration from Hyundai in order to resolve a P2096 fault code. See this thread: https://bobistheoilguy.com/forums/ubbthreads.php/topics/4425564/2013_Hyundai_Elantra_-_P2096_-
The results are almost too good to be true TBN of 6.7 (new is 9.0), Flashpoint of 435F and Insolubles of 0.1 after 7,400 miles is almost unreal.
How long can this oil go for?