Trans fluid leak at rear of case
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Trans fluid leak at rear of case 
I have a 1998 k2500 with 4l80e which is leaking fluid out of the bottom hole at the rear of the transmission case right under the output shaft. Is this normal? It is 4wd and from my understanding the union between trans and trans case should be dry. This leak comes out between extension housing and trans case and leaves a really big puddle in no time.
There should be a seal on each unit. Most of the time when you get fluid dripping from the weep hole means that one of the seals are bad.Isn't there a big O-ring that sits in the grove?
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Seal/Wet connection Yes there is an O-ring that fits on extension housing. Just got a new one in the mail about to put it on and back together to see if it remedies the issue.
On 4WD the transfer case to transmission connection is a dry unlike a 2WD which is wet. If you notice there is plug to the right of the output shaft. If this was a 2WD that plug would not be there. A lube orifice would be in its place, which kinda looks like a plug but it has a tiny hole in the middle.
Im hoping this new o ring is gonna make a difference.
On 4WD the transfer case to transmission connection is a dry unlike a 2WD which is wet. If you notice there is plug to the right of the output shaft. If this was a 2WD that plug would not be there. A lube orifice would be in its place, which kinda looks like a plug but it has a tiny hole in the middle.
Im hoping this new o ring is gonna make a difference.
If this is a 4X4 unit the cup plug with the oring is blocked by the 4x4 adapter, The upper and lower "Weep" holes are supposed to be plugged with steel cup plugs, It appears this case was originally 2wd application. Get 2 cup plugs "tiny freeze plugs" the 4l80e kit usually has them in it and put in the upper and lower holes and your issue will be solved .
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Yes there is an O-ring that fits on extension housing. Just got a new one in the mail about to put it on and back together to see if it remedies the issue.
On 4WD the transfer case to transmission connection is a dry unlike a 2WD which is wet. If you notice there is plug to the right of the output shaft. If this was a 2WD that plug would not be there. A lube orifice would be in its place, which kinda looks like a plug but it has a tiny hole in the middle.
Im hoping this new o ring is gonna make a difference.
On 4WD the transfer case to transmission connection is a dry unlike a 2WD which is wet. If you notice there is plug to the right of the output shaft. If this was a 2WD that plug would not be there. A lube orifice would be in its place, which kinda looks like a plug but it has a tiny hole in the middle.
Im hoping this new o ring is gonna make a difference.
