High Quality Content by WIKIPEDIA articles! Jaguar`s independent rear suspension (IRS) unit has been a common component of a number of Jaguar production cars since 1961, passing through three major changes of configuration up to 2003 and still used in the full-sized Jaguar XJ (in third generation form). This article concentrates on the first generation Jaguar IRS, which firmly established the marque`s reputation for suspension sophistication, combining as it did smooth ride with excellent roadholding and low levels of noise, vibration and harshness (NVH). The three generations overlap in time due to their being used in both full size and sports models that were updated at different times. The modern S-Type and XF models, although they are also rear wheel drive with independent suspension, use the Ford DEW98 platform so are not covered in this description of Jaguar`s in-house suspension systems.