Definately get Haldex filter & oil changed if its not been done for 2 years, its not that much and can prevent issues in the future.......I'd also get the rear diff oil changed and gearbox oil changed at your mileage.
Did both of mine at around 29,000/ 5 years and both were really dirty
Did both of mine at around 29,000/ 5 years and both were really dirty