Transmission fluid leak from INSIDE 16 pin transmission connector

Hey all, needing some direction here. My 2012 Tahoe has been leaking fluid from INSIDE the bulkhead/16-pin connector at the rear of the transmission. I have seen other threads where the connector has started to weep fluid from around the exterior of the connector, but this is definitively leaking from inside the connector.

Because that connection is weather/waterproof, it will collect transmission fluid inside and eventually short out the connection fooling the PCM into thinking it has a loss of communication with the transmission and resulting in the associated symptoms. This is confirmed by code U0101 which will self-resolve once I disconnect the 16-pin connector, clean the accumulated fluid out, and then reconnect it.

So my question is, can I replace the interior transmission harness from that connection to the TEHCM or valvebody, or am I looking at a really significant repair from a transmission shop?

I've included a picture of the bulkhead connector with an arrow pointing to pin 5 which appears to be somewhat discolored. Not sure if that's normal, or if this is a result of the fluid shorting out the connection.

Pic

I’m almost positive the connector sleeve will fix your problem.


https://www.amazon.com/ACDelco-2423...-Electrical/dp/compatibility-chart/B004JBE6L0

91RS said:

I’m almost positive the connector sleeve will fix your problem.

https://www.amazon.com/ACDelco-2423...-Electrical/dp/compatibility-chart/B004JBE6L0

Click to expand...

That guy's videos are amazing. I used one of his to help me rebuild a ZF 5HP-24 out of a BMW 740iL on the bench.

Looks like the part about the sleeve you're referring to starts at 2:25. I agree with your assessment as well.

Thank you for the responses. I'm going to order that sleeve and try it out. Any thoughts on the discolored pin(s)? I don't know if the discoloration makes a difference, though I will say that I cleaned the plug out last night and hooked it back up, and it's still registering a loss of communication with the trans. I'm wondering if I should just look into a valve body replacement to eliminate any question.

Geotrash said:

That guy's videos are amazing. I used one of his to help me rebuild a ZF 5HP-24 out of a BMW 740iL on the bench.

Looks like the part about the sleeve you're referring to starts at 2:25. I agree with your assessment as well.

Click to expand...

As an update, I replaced the sleeve you referenced, and it appears to have fixed the leak issue. Thank you for your help.

kronus said:

As an update, I replaced the sleeve you referenced, and it appears to have fixed the leak issue. Thank you for your help.

Click to expand...

Thank you for following up- that will help others in the future. Glad the part solved the problem for you!

kronus said:

As an update, I replaced the sleeve you referenced, and it appears to have fixed the leak issue. Thank you for your help.

Click to expand...

I replaced this sleeve twice already but fluid is still apparent INSIDE the connector as your original post stated. There isn’t fluid leaking from the exterior of the passage sleeve where the two washers are. Is fluid supposed to be inside and help with conductivity? I’m so confused.

You may or may not get a response from a 3 year old post.

denalianyone said:

I replaced this sleeve twice already but fluid is still apparent INSIDE the connector as your original post stated. There isn’t fluid leaking from the exterior of the passage sleeve where the two washers are. Is fluid supposed to be inside and help with conductivity? I’m so confused.

Click to expand...

I was actually not successful when I replaced that sleeve. I thought I was, but after a month or two, I noticed more fluid back inside the connector, and finally it got so bad that I couldn't even start the truck.

Took it to a shop and they ended up replacing the sleeve (again) and they replaced the connector plus about 8" of harness and I haven't had an issue since.

I have heard that you really have to make sure that sleeve is seated well. Without a lift, I'm guessing that I just was not able to get that sleeve to seat correctly.