Transmission Fluid Vent
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Joined: Dec 2003
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From: Horncastle Lincolnshire, England
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Transmission Fluid Vent
I posted a thread about my great experience with a LV Dealer. 
The problem was a vent on the transmission dumping fluid overboard.
Any of our tech gurus know what this vent is and why it does that. Is it just to protect from overfilling?
The problem was a vent on the transmission dumping fluid overboard.
Any of our tech gurus know what this vent is and why it does that. Is it just to protect from overfilling?
than I thought
Pro
Joined: Jun 2004
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From: Avondale AZ
No transmission vent, however there is a rear end vent. I have an '04 A4 and it was overfilled from the factory. The dealer drained some and all has been fine since. I noticed you are in LV. I'm in PHX and with the heat and the heat build up in the rear, expansion occurs and if overfilled it will vent out. 
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Joined: Aug 2001
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From: King George VA
I am not aware of a tranny vent either, but there may be one. I know the diff has a vent on the upper driver's side. This vent is to allow relief of excess pressure caused when the diff heats up and the fluid expands. I get some fluid out of that vent when I track my car. 
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Thread Starter
Tech Contributor
Joined: Dec 2003
Posts: 19,384
Likes: 87
From: Horncastle Lincolnshire, England
2023 C5 of the Year Finalist - Unmodified
Originally Posted by P51tj
No transmission vent, however there is a rear end vent. I have an '04 A4 and it was overfilled from the factory. The dealer drained some and all has been fine since. I noticed you are in LV. I'm in PHX and with the heat and the heat build up in the rear, expansion occurs and if overfilled it will vent out.
