Are you wanting to learn how to change transmission fluid in your vehicle or just want to understand how it is done? It's really not all that complicated of a procedure. We'll start with preparing the vehicle for easiest removal of the transmission fluid pan. You're going to have to get underneath your car or truck to do this job properly so we'll start by positioning the vehicle on a level surface. Then you'll need to apply the parking brake and jack up the front end of the vehicle and put jack stands underneath the front part of the frame for proper support. After you are done supporting the vehicle for your safety you will need to slide underneath the vehicle and take a look at what you're going to need. The transmission pan may possibly be covered by a skid plate, especially if your vehicle is a 4X4. If you do have a skid plate, there should be just a few bolts attaching it to the vehicle, of which will have to be removed. If you don't have a skid plate, you can find out how many and what size bolts are holding the transmission pan to the transmission housing. Some vehicles have transmission drain bolts to remove transmission fluid. If your vehicle has a bolt in the bottom of the pan, you may want to go ahead and drain your transmission fluid at this point by removing that bolt. If you don't see a bolt, you will need to remove the bolts that hold the transmission fluid pan on. For easier clean-up, you may want to lay down a piece of cardboard underneath the pan, because fluid may spill onto the ground if you are not careful. As you are removing the bolts, work away from a corner so that as the more bolts you remove, the more that corner starts to "sag" and funnels the oil into your collection container sitting below. Then once you are getting close to removing all of the bolts, you can hold the transmission pan up with one hand while removing the remaining loose bolts with your other hand. After all of the bolts are removed from the pan, carefully lower the transmission fluid pan down to your collection container and pour the remaining transmission fluid in the pan into the container. Thoroughly clean the pan and any bits of gasket material off of the transmission fluid pan. Now get back up under the vehicle and check the gasket surface on the transmission housing. Make sure nothing is left behind, but a slick surface. You can use a razor blade to remove gasket material, but be very careful not to cut yourself or into the transmission housing gasket surface. Now that the surface of the transmission fluid pan and housing surface are good and clean, you need to remove the transmission filter. It is usually held into place by 2-4 screws. Remove the transmission filter and replace with a new one of the correct size with the same bolts used to remove the old one. Now we're ready to replace the transmission fluid pan with a new gasket. You can use a sticky gasket adhesive to hold the gasket in place as you replace the fluid pan to the housing surface, just make sure all of the bolt holes between the gasket and gasket surface line up evenly before applying it to the gasket surface. Now you should be ready to replace the transmission fluid pan to the transmission housing. Hold the pan up with one hand while you thread the bolts in with the other hand. Be sure that none of the bolts crossthread. Once all of the bolts are in and you have made sure none of them are crossthreaded you can tighten up the bolts just snug all the way around. Now you're ready to add transmission fluid. Add the correct amount of tranmission fluid that your manufacturer specifies for your vehicle and start the vehicle up to check for leaks. If no leaks are found, wait for the vehicle to warm up and check the dipstick to make sure the transmission fluid is at the Full level. Once you are done, remove your vehicle from the jack stands and lower the vehicle back to the ground and remove the parking brake. You now know how to change transmission fluid.