How to Change Your Jeep’s Automatic Transmission Fluid SHARE How to Change Your Jeep’s Automatic Transmission Fluid We use a 1999 Jeep Cherokee XJ to highlight some tips for doing a fluid and filter service on your Jeep’s automatic transmission. Christian Hazel – Mar 11, 2021 For us, there really isn't a maintenance job we like doing less than changing the fluid and filter in an automatic transmission. Even if you're blessed with an automatic that has a transmission pan with a drain plug, it's frustrating. And if your tranny pan doesn't have a drain plug, be prepared for ATF to cascade all over your driveway and yourself. But it's something you need to do if you want continued good performance and extended life. So using a 1999 Jeep Cherokee XJ with a 4.0L engine, AW4 transmission, a swapped in NP231, and a factory exhaust downtube as an example, here are some tips to consider when changing your Jeep's automatic transmission fluid.