Help with fluids.....

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Apr 9, 2010 | 02:04 AM

BlackFya

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Pro

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From: Durham North Carolina

Help with fluids.....

I have a 2000 A4 with 3.15 rear end. I want to change the fluids soon. Is full synthetic ok for the A4 and differential? I've heard mixed reviews on the synthetics being bad for auto trannies. Thoughs and recommendations please!

Apr 9, 2010 | 06:44 AM

Cybermind

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I used Mobil 1 synthetic ATF in the tranny and GM synthetic diff fluid with the GM additive in the diff. I heard that the GM stuff is excellent diff lub.

As far as the tranny is concerned, I have a MN6 so I can't really comment on whether Mobil is good for automatics. But, I don't see why it wouldn't be since it meets Dexron III requirements. All I know is that my manual tranny now shifts like butter.

Last edited by Cybermind; Apr 9, 2010 at 06:47 AM.

Apr 9, 2010 | 11:44 AM

Rohan

Burning Brakes

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I put the Valvoline Dexron VI in my car...did it myself. The car shifts much better and handles High Temps better. Since Dexron III is no longer licensed I don't really trust DEX III. And GM recommends the DEX VI.

For your diff fluid a lot of guys (including myself) like the Royal Purple Max Gear No additional additives needed.

Last edited by Rohan; Apr 9, 2010 at 12:02 PM. Reason: Referenced a MN6. Discussion is about an automatic.

Apr 9, 2010 | 11:46 AM

lucky131969

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From: Dyer, IN

Quote:

Originally Posted by Rohan

Mobil 1 is too slippery.

Could you explain that in layman's terms?

Apr 9, 2010 | 12:00 PM

Rohan

Burning Brakes

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Quote:

Originally Posted by lucky131969

Could you explain that in layman's terms?

Lucky,
I meant to delete that. I hastily read through his post and started to type that in reference to the synchros in a 6 speed (he is talking about an automatic).

In my experience: I would once in a while get a grind going into 1st. Problem never happened again after going to a normal dexron III fluid. Also, my 3-4 synchro wore out to and I dont drive my car hard. I asked a few guys why this was and they told me that with Mobil 1, the synchros get too hot.

I'm sure people will go round and round about this but that was my personal experience. Go with what you know I guess. Let me know if I've been misguided.

Apr 9, 2010 | 12:13 PM

lucky131969

Tech Contributor

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From: Dyer, IN

Quote:

Originally Posted by Rohan

I asked a few guys why this was and they told me that with Mobil 1, the synchros get too hot.

Hmmmm....that's interesting. One would think that if a fluid contained properties that reduced friction....heat would decrease as well (at least that specifically related to friction).

I will continue to use Dexron III. If I was doing auto-x events, I would consider another fluid. For a street driven car, the factory recommendation is fine. Observing a fluid change schedule is key.

Apr 9, 2010 | 12:24 PM

Rohan

Burning Brakes

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I was thinking that the slippery characteristics in a synthetic are not conducive to synchros working properly but at the same time what you told me about them preventing heat makes sense too. Maybe I just had a bad tranny? Also, synthetic is a friction modifier and the tranny syncros work on friction... this could be an argument but I would say that if it meets Dex III specs then this would indicate it provides the same friction properties as non-synthetic. lol, I guess what I'm getting at is that maybe everyone gets different results for whatever reason. Anyway, you know I would never argue with you Lucky. I just want to learn as much as I can.

Apr 9, 2010 | 02:43 PM

lucky131969

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From: Dyer, IN

Quote:

Originally Posted by Rohan

Anyway, you know I would never argue with you Lucky. I just want to learn as much as I can.

I hope you would if you thought I was full of $hit.....or just plain wrong. Arguing aside.....I think discussion is healthy, and challenging opinions is healthy.....especially when they are based on hearsay....not facts.