September 10, 2005i have a 2002 sierra 1500 2wd with an automatic trans. i was planning on changing my trans fluid and filter. i have 52,000 miles on it. the manual says only change if you have an allison trans, gvw of 8600 lbs or if driven under harsh conditions. otherwise don't change until 100,000. i don't think i have an allison trans, but how can i check to be sure, i do all highway driving and i don't think it weighs over 8600 lbs. if anyone can give me some info that would be a huge help.
September 22, 2006allison is for the diesel you should have a 4l60e and it will never hurt to change it out anyways. may as well put in a transgo kit while you have the pan off
September 22, 2006http://www.gmdiy.info/portal/index.php?option=com_content&task=view&id=62&Itemid=26