Author Topic: What is this and its function?  (Read 2316 times)

Offline philo_beddoe

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What is this and its function?
« on: April 13, 2017, 09:53:51 AM »
I dont have a pic yet, but its a black hose coming from top of rear diff and attached to bottom of bed. It has a plastic button type thing that pushes in and out.
Behold, the day of the LORD cometh, and thy spoil shall be divided in the midst of thee.  Zechariah 14:1

Offline csdineley

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Re: What is this and its function?
« Reply #1 on: April 13, 2017, 09:55:39 AM »
Vent tube.
1987 V20 Custom Deluxe, Vortec Headed 350, SM465,Np205 14Bff 4.10

Offline VileZambonie

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Re: What is this and its function?
« Reply #2 on: April 13, 2017, 12:48:34 PM »
It's a breather connected to the vent hose.
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Offline philo_beddoe

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Re: What is this and its function?
« Reply #3 on: April 13, 2017, 02:09:58 PM »
Does air go both ways or just vent out?
Behold, the day of the LORD cometh, and thy spoil shall be divided in the midst of thee.  Zechariah 14:1

Offline GMCMedic

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Re: What is this and its function?
« Reply #4 on: April 13, 2017, 06:43:46 PM »
What they said

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Offline philo_beddoe

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Re: What is this and its function?
« Reply #5 on: April 13, 2017, 10:25:02 PM »
Got it...."vent"
Behold, the day of the LORD cometh, and thy spoil shall be divided in the midst of thee.  Zechariah 14:1

Offline VileZambonie

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Re: What is this and its function?
« Reply #6 on: April 14, 2017, 07:29:56 AM »
It's designed to allow venting as the axle and lube heats up. As it cools, a negative pressure closes the valve. For normal use they are fine but can fail which typically leads to failed axle seals, pinion seals, water intrusion etc. Some people prefer to run a small filter vent with no valve and a relocated hose if they do off-roading or mud bogs. Unless you are seeing leaks and water intrusion, just leave it be.
,                           ___ 
                         /  _ _ _\_
              ⌠ŻŻŻŻŻ'   [☼===☼]
              `()_);-;()_)--o--)_)

74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline philo_beddoe

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Re: What is this and its function?
« Reply #7 on: April 14, 2017, 10:32:01 PM »
No leaks or water, it was grimy, so i just cleaned it up.
Behold, the day of the LORD cometh, and thy spoil shall be divided in the midst of thee.  Zechariah 14:1