Yes, well I was under the impression that Dex was maintenance free and upon reading the reply from RareGmFan I learned that it does in fact need maintenance every 5 years or 150k. I personally don't use it And the first thing I did to my car in 2009 when it was purchased was flush out the Dex and poured in a 50/50 mix of green. This is from personal experience as I saw my moms 2001 GTP with 10k on it gum up in 2002 and need an entire flush and front head gasket.