4L60E transmission, what is the purpose for the weep hole?

1994 GMC C1500
180,000 MILES • 5.0L • V8 • 2WD • AUTOMATIC
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CARHOP
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I am doing a fluid change on 4L60E transmission. After removal of the transmission pan, I noticed a "weep" hole on the passenger side gasket surface of transmission housing. After leaving transmission to drain overnight I see droplets of transmission fluid fall through that hole every few seconds. I would like to button up the transmission pan but think the gasket will leak because the surface is not dry. What is the purpose of this hole? What is the best course of action? Thank you.
Aug 28, 2022 at 9:36 AM
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JACOBANDNICKOLAS
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Hi,

There shouldn't be a weep hole on the pan surface area. Is it actually where the gasket will sit? Can you upload a pic of it so I can see exactly what you are referring to?

I can tell you that the valve body will drip for a long time. It is frustrating when trying to dry the pan surface and get it together before it gets wet again. I just always dry as much as I can and then quickly install the pan.

I attached a pic below. If you can't get a pic of yours, copy my pic and circle or highlight where you are referring.

Let me know.

Joe

See pic below.
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Aug 28, 2022 at 8:28 PM
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CARHOP
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The hole is 1/16" in size, located between pan bolts #1 and #3 where the gasket will sit. It stopped leaking and I installed the pan. Could not get a pic. Thank you.
Aug 29, 2022 at 2:56 AM
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JACOBANDNICKOLAS
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Hi,

Is everything okay now that the pan is reinstalled? I'm not sure what you were seeing, but if there was a weep hole there, the pan would constantly leak.

Regardless, let me know if everything is okay.

Take care,

Joe
Aug 29, 2022 at 6:06 PM
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CARHOP
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I found some pics online. The hole is between #3 and #5 bolts in the torque sequence. Could not find any information on it. Interested in finding out its purpose. Pan is not leaking. Thanks for your help.
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Aug 30, 2022 at 2:38 AM
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JACOBANDNICKOLAS
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Hi,

I copied your pic and circled what I think you are referring to. If that is correct, that is a drain that allows fluid to return to the pan.

Let me know if I got the right place.

Take care,

Joe

See pic below.
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Aug 30, 2022 at 6:53 PM
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CARHOP
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Thank you for the information.
Aug 31, 2022 at 3:01 AM
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JACOBANDNICKOLAS
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Hi,

You are very welcome. I'm glad to know it's back together and working properly.

Please feel free to come back anytime in the future if you have questions. You are always welcome here.

Take care,

Joe
Aug 31, 2022 at 6:09 PM