Some trans. pans have drain plugs. If it does,remove plug and drain into a pan large enough to hold 8 quarts or more. If it doesn't have a drain plug, you will need to put your drain pan under one of the front corners and start removing the pan bolts in that corner working your way in both directions removing bolts till you reach the opposite corner. Next you need to remove the shift cable and bracket. The pan will come out between the cross-member and valve body with some effort. Remove the filter. If you buy an AC Delco filter,it will come with a new seal that pops in where the filter came out of,but if the seal didn't come out with removal of the filter than you don't need to change it. Push the filter up in place,make sure its seated all the way. The pan gasket is re-useable,just clean the pan and all sealing surfaces and put back in place. I don't have the torque spec. on the bolts but remember the gasket is rubber-don't overtighten. Put the shift cable and bracket back on,pull the dipstick,and put in 5 qts. dexron III. Start the engine,put your foot on the brake,run trans. through all the gears several times.Put in park and let engine run awhile,check fluid level a few times and add till its on the full cold mark. Drive it about 10 miles or so and check again(fluid expands) so check it several times to make sure level stays between full cold and full hot.How to change transmission fluid on 2004 gmc yukon?
Pay to have it done IMHO. Many shops have a flush machine to change all the fluid, if you do it yourself you wont be able to get it all out easily. This service is usually competitively priced so if you look around you should be able to get it done for a reasonable price. Its a pretty messy job unless you have a 3/4 ton with a 80 series or allison transmission, those have plugs so its slightly easier but you still only get whats in the pan. Much of the fluid is in the torque converter.
