Originally Posted By: ChrisD46
MileHigh18 & others : I Just picked up a used '02 TB LTZ (2WD) with 80K miles on it - while most fluids looked good , the ATF was dark reddish brown so I assume it has not been changed before . Do you know the first ATF recommended drain & fill schedule for that TB , how many qrts. it approx. takes for a drain & fill and lastly the drain bolt size ? Thank you for any details you can provide !
11.3 quarts is a full ATF change, and a filter change and pan drop gets out about 5qts according to the owner's manual. I just bought mine 2 months ago, and I've changed the fluid in the front and rear diffs, and changed out the transfer case fluid as well. If you're unsure whether or not the services have been done like I am, go ahead and do them ASAP. I just got my tranny filter today and plan on doing a pan drop and filter change. I plan on using Super Tech Dexron VI which is 4.27 a qt at our local WalMart. I'm gonna pick up 6qts just to make sure I have enough, but like I said, the owner's manual states 5qts for a pan drop.
There is no drain bolt for the transmission pan unfortunately, unless the previous owner of your trailblazer added one to the pan. You just have to loosen the bolts so one end sags and starts to allow fluid out. The rear diff has a drain and fill bold, and all that takes is a 3/8 drive. Rear diff holds 2qts, I use Mobil 1 75w-90 full synthetic, and front holds a little under 1qt but I went ahead over filled it by a hair. Also note that some Trailblazers have a deep tranny pan and some have a shallow pan. Make sure you figure out what pan you have before you get your filter. Hope this helps. Any other questions, just let me know.