It has taken me 3 years to finally get the Transgo kit in my transmission. At the same time I replaced lower control arms, brake rotors and pads. To say that the effort was worth it is an understatement! It is not the same car and I don't know why it took me almost 3 year to get around to it. Now down to brass tacks, I finished the job and then read something about using Dex 6 to refill the trans. I used Dex 3. Am I going to have any problems by using the Dex 3?
Dex 3 in a 2005
- Thread author elmor
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ulycyc
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DEX3 is what was used in 2005 and GM superseded it with DEX6 a few year later for repairs and refills. Will Dex3 hurt anything and must be drained? NO. Your next service (filter/fluid) change use DEX6
RD_Atlanta
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I've used both on different cars throughout the years. I used 6 on the three Lesabre's that I currently own when I installed the shift kits (since 3 is getting more difficult to find and as MelsRegal said, 6 is supposed to be the sanctioned replacement). My own experience is that both worked well.
Thank you all for the answers! You guys really helped me a lot!
When I dropped the transmission pan, I discovered that someone before me had just sort of... left out the filter when they put the pan back on! I was beside myself. Why in the world would someone go through the trouble of draining the pan and not put in a new filter?! Oh well, it has one now and the trans is working better than ever.
When I dropped the transmission pan, I discovered that someone before me had just sort of... left out the filter when they put the pan back on! I was beside myself. Why in the world would someone go through the trouble of draining the pan and not put in a new filter?! Oh well, it has one now and the trans is working better than ever.
Buick City Bert
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My wife's 2005 Lesabre called for DEX III, always used DEX III for 2 change outs, never had a problem, could see no reason to change.
The 2008 Lucerne asks for DEX VI, changed it out, used Valvoline synthetic DEX VI, added lube-guard at recommend from friend in the Trans shop, 50 K miles and ready to do it again at 100K miles on the car and have had zero issues with the trans. My understanding is the main difference between DEX III, and DEX VI is the higher temperature rating.
In my experience regular changes of the fluid and filter make good transmissions stay good to at least 200k, my 92 Roadmaster Trans went to 300k even with occasional teenage drivers, using DEX III.
The 2008 Lucerne asks for DEX VI, changed it out, used Valvoline synthetic DEX VI, added lube-guard at recommend from friend in the Trans shop, 50 K miles and ready to do it again at 100K miles on the car and have had zero issues with the trans. My understanding is the main difference between DEX III, and DEX VI is the higher temperature rating.
In my experience regular changes of the fluid and filter make good transmissions stay good to at least 200k, my 92 Roadmaster Trans went to 300k even with occasional teenage drivers, using DEX III.
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