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Discussion Starter #1
So I've been debating switching tranny fluid from the VW mineral stuff to redline D4. I figure if the torque converter is being taken off then I should be able to drain 90% of the OEM fluid. The only concern is that it is going to cost me $200 for a case of the redline stuff. I also have a line on pentosyn fluid for about $150 a case. I know from searching the forums that some of you have had good experiences with the D4 fluid but what about pentosyn? Any info on experiences with these two brands or others would be welcome.
 

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Honestly, I wouldn't mess around with your transmission more than you already have. If you've used Pentosin in it its entire life, then Pentosin is what's embedded in the outer atomic layers of the parts. Who knows what adding a different fluid could do to the friction parts on a molecular level.

The shop manual from my old Mazda even says explicitly never to change fluids mid-lifetime, and when replacing worn-out parts, let the new parts soak in a tub of fresh fluid for 48 hours before installing. Granted, they're not the same transmission, but I doubt they'd have mentioned such small details unless it really did matter.
 

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Discussion Starter #3
Granted, but this tranny only has 20000mi on a total rebuild. What interests me the most about the D4 is the fact that it is synthetic and looks to offer better resistance to varnishing/glazing of the clutch packs. As much as I see the logic to keeping the OEM fluid in the tranny the fact that I can't ignore is that the OEM fluid was spec'd for use in a transmission environment where the heat generated was only equivalent to 150hp and more importantly 150ft/lb. Now some may argue that other audi trannies use the same fluid (assuming that they do, I'm not sure) but they also have more clutch material to cope with the higher loads. I guess the biggest question I have is that has anyone here seen any documented or even anecdotal transmission failures associated with D4 and what were the conditions surrounding them (mileage, engine tune etc...)
 

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that was printed for fear of shocking the system. because mid-lifetime can be easily misinterpreted as 100k miles on a car you want to live at least 200k miles.

by shocking, i mean causing the new detergents to knock too much crap loose. ie. the clutch material.

the purpose of soaking the materials in the fresh atf is to make sure that it will not get burned up or rip apart on it's first run. building transmissions is a very messy job because of this. last i did it, i was basically sloshing the atf over everything :lol:
granted it was a nissan transaxle 80X17
 

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Discussion Starter #6
So does this mean you're one of the few people that has actually taken apart an automatic tranny? If so, props to you. I figure that the thermal resistance that the D4 has will allow me to put off the aux cooler for a little while (I'm already spending waaay too much on this) since average temps are around freezing for the next couple months. I also take some comfort in knowing that Dpassat00 is running a stroked 2.0 big turbo setup with only a TC and valve body upgrade. Hell maybe I'm being paranoid about this whole thing. Then again as I said in another post, maybe my paranoia is just the acute sensation of knowing that I'm right.
 

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Discussion Starter #8
Yeah, I've learned to trust that little voice in the back of my head. As for the rest of the voices I just put tinfoil on my head to block the CIA transmissions:lol:
 
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