Genuine OEM Detroit Diesel oil cooler core (10-plate design), part number 23522416. Fits Series 50 (8.5L) and Series 60 (11.1L / 12.7L / 14.0L) engines. NOS (new old stock) condition in original packaging. No core charge or return required. Price is firm as listed unless “offers” enabled. Unsolicited discount requests will be ignored; repeated messaging may result in blocking. Clear evidence of part swapping or fraud? Honest mistake or fitment question? Happy to work it out!