NP241 is making fluid

[eodcoduto]

The transfercase in the Suburban has leaked since I got it and I replaced the rear output seal but it still leaks, it needs the bushing done, and the case leaks. But I've never checked it because if it leaks it has fluid! But the transmission looses a quart every couple of months so today I pulled the fill plug on the 241 and about 2 quarts of ATF came out. So now I know where the transmission fluid is going. Is the gasket between the 4l80e and the NP241 they only way the fluid can transfer? 1991 V2500 Suburban that I daily drive, every day and I put around 1000-1200 miles a month on it.

 

[Fastereddie]

The input shaft seal in the 241 is bad.
Very common issue

 

[Wes Harden]

Before you do the seal between the Trans and the case make the Trans vent line is clear. If it's not and you get it cleared out both leaks might stop

 

[eodcoduto]

I’ll check that tomorrow!