4L80E Front Seal Failure

cw41

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#1
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MAKE:Chev
MODEL:Silverado 2500HD
YEAR:2003
MILES:110,000
ENGINE
:6.0
DESCRIBE ISSUE....4L80E Front Seal Failure
 

cw41

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#2
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MAKE:Chev
MODEL:Silverado 2500HD
YEAR:2003
MILES:110,000
ENGINE
:6.0
DESCRIBE ISSUE....4L80E Front Seal Failure
My son in law bought a rebuilt 4L80E from what he thought was a reputable shop in texas, built to his specs with towing capacity for toy hauler, future engine upgrades, gearing, tire size, etc. He had a certified mechanic of 20yrs install with the same companies torque converter and installed a larger trans cooler. It was supposed to be built for smooth shifts but it would kick him out of the seat. Then, after 300 miles while towing his toy hauler, the trans starting loosing fluid everywhere. After a tow home and loaded on car trailer, he went back to his mechanic which he is a personal friend, found the front seal had pushed out from the pump and ground up contamination everywhere. The Texas company says poor installation of the torque converter caused this. I know you can try to install a tranny without the converter seated where it should be and try to bolt it up and have a mess but the mechanic is smarter than that. How can the front seal blow out like this? Of course they won't provide any warranty. Any ideas on what might of happened here? Thanks again for your time to reply.
 

billr

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#4
I'm going to PM BP, see if he will make a visit here and provide some expert advice.
 

bp042665

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#6
What has happen is it either got to hot and pushed out or the pump bushing has spun and walked it out whats the snout on the converter look like is it smooth and shinny or does it show wear
 

cw41

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#7
I'm waiting for the mechanic to send me the pictures but there was some sort of converter failure. I'm sure it got hot but this truck has a tranny temp gauge and he's good at watching it when towing. the mechanic said if it was just a bad pump seal, the new he tried fit loosly so it wouldn't stay in either. I'm thinking the front pump seal area is defective?? the mechanic just tested this, no way was a new seal going to fix the problem. I'll contact my son in law and ask him about the snout maybe he got somemore pics. thanks for the help
 

nickb2

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#10
Unless the front pump is cracked, I just install a new seal. It comes with the rebuild kit.

Or look for blockage, cuz that seal is not leaking for nothing. This is not a backyard job unless you have tools and skills.
 

nickb2

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#11
A convertor failure can happen. But in 22 yrs in this trade, I have never seen a torque convertor blow front seals unless something broke or is worn out.

I prefer when they blow out on the strip, but hey, I have done my fare share of drag racing and car repair. If that leak is still present after proper repair. Something is wrong and need to investigate more. $.02
 
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cw41

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#13
Hey Nickb2, remember my black cat overheating Impala, now my son in law has a black ca.t 2500! When he got the tranny installed, it was supposed to be set up for HD towing and performance with a relatively smooth shift, but it would kick him out of the seat. Lasted 300 miles before it blew the front seal out and they say it's improper torque converter install? What a crock. They won't stand behind their warranty so maybe the BBB can help?? There was a huge amount of ground up something in the pan so Its a classic transmission failure, not improper installation. We'll see how it plays out wish I could pay them a visit!
 
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#14
4th of July weekend, 400 miles from home when the front seal of my P-30 motorhome gave out, pouring fluid out like crazy. Found an opened Auto Zone store, Lucas AT seal restorer got me home. Doubt if this would have helped your son-in-law.

Seems like the rebuilder is to blame on this.
 

cw41

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#15
I think the rebuilder is to blame also, 3600.00 plus install labor for 300 miles would be embarrassing if I would have done the job.