Hi all.Quick question about DexIII and DexVI, before you flame me for not searching I have and get mixed answers. My car is at 89,000 miles and I will be driving to Dallas this weekend. While I'm in Dallas I plan on changing the ATF. I would have liked to drop the pan and do a filter swap but logistics prevent me from doing so, plus I changed the filter at 60 K. Instead I will be using a mityvac to suck the fluid out from the trans fill tube and I already know that this method will only pull 40% out. I have already ordered 2 gallons of AC Delco DEX VI, and plan on doing the fluid exchange twice. Is this adequate? I'm well aware that Dex VI is backwards compatible with DexIII but have also heard that in some Allison transmissions DexVI can cause leaks. I'm also concerned that the remaining DexIII will cause issues. Am I overthinking this?car is a 2005 GTO mainly city driving with occasional high speed stints. TIA
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