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4l80e Vent / Dipstick issues. Leaks?

dhcomp

dhcomp

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Ok, so my truck has always had ATF scattered around the underside. For as long as I can remember. What i thought was the trans vent, ended up being the transfer case vent, and clearly lets fluid out fairly frequently.

Before getting the trans built, i dont' remember having any leaks besides the transfer case output. When the trans was built, the transfer case was resealed, and the seals between the trans and transfer case were replaced.

While under there today, I realized that nothing is hooked up to the Trans vent tube :eek1:.

Picked up some hose, ordered up some breather filters, and plan to extend all my vents up into the Engine Compartment.

After trying to investigate where all the fluid was coming from, i decided I better make sure the trans vent wasn't plugged. Hooked up a hose, and blew into it. It seemed to take air, and all of a sudden, i was getting an ATF shower. (The 2nd one of the weekend, the first being trying to fill the "non serviceable" "Lifetime trans fluid" transmission on my dad's bmw :haha:)

Tried to figure out where it was coming from, and couldn't. Top of the dip stick was sealed, but it was coming out high, and dripping down the top of the bellhousing. Moved the drop light, blew on the vent again, and found fluid gushing out of the front side of the dipstick tube, about 1/2 - 3/4 of the way up.

Now, the question. Is there supposed to be some sort of vent hole here? I woudl think not, due to the fact that you fill through this tube, and that the dip stick is sealed at the top.

Anyone?

Ordered a new dipstick tube from Rock auto, i guess we'll see what happens when it shows up!

Thanks guys!
 
When blowing in the vent line I'm sure you could pass air into the trans. I'm not sure why you would leak fluid out the around the seal on the dipstick.

The vent line for the Tcase runs up the back of the trans and the vent is tied off near the top of the firewall.
 
I'm not leaking fluid out Around the dip stick, there is actually a hole in the side of the dipstick tube About 1/2 way up.

My current transfer case vent only makes it up about 1/2 way to the firewall. This will be getting extended soon
 
dhcomp said:
I'm not leaking fluid out Around the dip stick, there is actually a hole in the side of the dipstick tube About 1/2 way up.

My current transfer case vent only makes it up about 1/2 way to the firewall. This will be getting extended soon
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Wow, that is strange. I've never seen that before. :eek1:
 
Does the tube still have the tab to locate it to a bellhousing bolt? If not, its probably broke off and now leaking where the tab tack weld was.
 
nvrenuf said:
Does the tube still have the tab to locate it to a bellhousing bolt? If not, its probably broke off and now leaking where the tab tack weld was.
Click to expand...

This??

I have never seen a hole in a dipstick tube. That's most likely your problem. Also, when you ordered the new dipstick, did you order just the dipstick, or the tube? Or both? Because if you ordered a dipstick you might get just the dipstick.
 
I don't think I've ever seen a tranny from the factory with any vent tube really. They usually just have a plastic elbow that is slipped in the little vent hole. I always run a 1/8NPT tap in there and thread a brass nipple in there, then run some hose up the firewall.

Can't say I've ever seen a dipstick tube with a hole in it either. I suppose it could be a vent to prevent ATF spraying on to the engine/exhaust manifold (fire hazard) in the event that the vent on top of the bellhousing gets plugged. I have read about some car fires being started this way, but this doesn't sound like a good way to fix it though.

Can you get a picture? I'm very curious...
 
folkenheath said:
This??

I have never seen a hole in a dipstick tube. That's most likely your problem. Also, when you ordered the new dipstick, did you order just the dipstick, or the tube? Or both? Because if you ordered a dipstick you might get just the dipstick.
Click to expand...


Ordered the tube from rock auto. I'll do a real inspection of the old one once i get it out. Wasn't worth draining the fluid to remove and inspect before i had another one on hand, for a $20 part.

I'll let you know what happens!
 
You guys win, 3 little holes where the mount ripped off.

And, no mount in sight. Trans guy must have broke/lost it.

And FYI, these 3 holes here really do no harm. I spent 5-6hrs tearing this MF'er out, and installing the new one.

If you ever get the itch to change a trans dipstick tube, while the trans is in the vehicle.....DONT.

Its not worth the hassle.
 
dhcomp said:
If you ever get the itch to change a trans dipstick tube, while the trans is in the vehicle.....DONT.

Its not worth the hassle.
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Huh? You can't really put the trans in with the dipstick in, it won't clear. I always pull the dipstick first on the way out and put it in after the trans is in anyway. Usually only takes a few minutes. I am sure some vehicles are tougher though.
 
folkenheath said:
Huh? You can't really put the trans in with the dipstick in, it won't clear. I always pull the dipstick first on the way out and put it in after the trans is in anyway. Usually only takes a few minutes. I am sure some vehicles are tougher though.
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Interesting. The only easy way i saw it was to install it before the engine.

I cut the bracket off my new one to make install easier.....and it was still damn near impossible.
 
dhcomp said:
Interesting. The only easy way i saw it was to install it before the engine.

I cut the bracket off my new one to make install easier.....and it was still damn near impossible.
Click to expand...

It actually is chalenging, but if I remember correctly the last time I slipped it in from the bottom, went easier.
 
That bracket is supposed to hold it in at the right height so you are checking the proper fluid level, as well as keep it from coming out and leaking fluid everywhere. I would never cut the bracket off. I have had to put them in from the top and bottom some with a lot of twisting, but they usually go in one way or another.
 
folkenheath said:
That bracket is supposed to hold it in at the right height so you are checking the proper fluid level, as well as keep it from coming out and leaking fluid everywhere. I would never cut the bracket off. I have had to put them in from the top and bottom some with a lot of twisting, but they usually go in one way or another.
Click to expand...


My understanding was if the "stop flange" on the tube, where it slips into the trans, is properly seated, i'm at the right level to check fluid.

There was no way that tube was going in with the mount on it, and I still don't know where that would have attached.

Yes, i installed from the bottom.
 
dhcomp said:
My understanding was if the "stop flange" on the tube, where it slips into the trans, is properly seated, i'm at the right level to check fluid.

There was no way that tube was going in with the mount on it, and I still don't know where that would have attached.

Yes, i installed from the bottom.
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The mount is attached behind one of your trans bolts. I'll see if I can get a photo of it tomorrow.

The tube would seem to be just floating around with out it. :dunno:
 
cuervo said:
The mount is attached behind one of your trans bolts. I'll see if I can get a photo of it tomorrow.

The tube would seem to be just floating around with out it. :dunno:
Click to expand...


Sorta. Its a done deal now. The old one was floating around too, probably for the last 30k.....

I zip tied it to some bracket on the back of the motor. :haha:
 
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