The rear fitting does have an oring from the factory.

 

Good, because I used the AN ebay pieces and im pretty sure It was O ringed. I didnt recall the factory being like that.

 

I know i am bumping an old thread but i thought i would post why that rear cooler line fitting is important and were it attaches in side the case.. As you can see it plugs directly in the center support

 

Awesome pictures corey! That shows how important it is.

 

Ya when you see it up close like that it really hits home.

 

Bookmarked

 

I have been told that the fitting can also extend too far into the center support resulting in poor lube. Can this happen? See how half the hole is blocked if you slide the fitting all the way in. There is definitely nothing going in there if you don't use the fitting with a nipple.

Center support with seal


Fitting inserted

 

Can we get this added to the GM drivetrain sticky list? I came from a 5speed so just did 6an hookups. This error likely had a large role in killing 2 brand name 4l80 builds and a ton of trouble/work/money from the builders to end user. Those who are new to these trucks/trans can easily overlook this.

 

Why do most of them fail but a few of them have no problems?
Like mentioned earlier, i went years on the wrong fittings and last time i had the pan off everything looked good.

 

does this apply to a TH400 as well?