I just used a liquivac to suck out 3 to 3.5 qts of ATF+4 from the 2005 Durango with 111K miles and it looked brand new... I couldn't believe it. No previous changes as the owners manual is horrible. no service recomendations unless you are a taxi or towing a lot. I replaced it with Valvoline ATF+4 which is supposedly fully synthetic. thought it was due for a re-fresh.