Forward input drum leak from case to input shaft - importance?
Thread Starter
On The Tree
Joined: Sep 2018
Posts: 161
Likes: 4
From: New Zealand
Forward input drum leak from case to input shaft - importance? Rebuilding a single piece 4l60e from a '97 camaro due to broken sunshell.
3-4 clutch packs were not to bad, considering the milage (approx 120k miles).
As per below video, after rebuilding the 3-4 input drum. You can see a hissing between the input shaft and the casing when applying approx 40psi.
There seems to be mixed opinions on the internet of the importance of a leak here. I purchased a refurbed input drum from ebay but it has the same leakage at that same point. Do you think I need to get another input drum (a third one), or do you think I will be OK with this one? I can see the clutches engage perfectly fine.
3-4 clutch packs were not to bad, considering the milage (approx 120k miles).
As per below video, after rebuilding the 3-4 input drum. You can see a hissing between the input shaft and the casing when applying approx 40psi.
There seems to be mixed opinions on the internet of the importance of a leak here. I purchased a refurbed input drum from ebay but it has the same leakage at that same point. Do you think I need to get another input drum (a third one), or do you think I will be OK with this one? I can see the clutches engage perfectly fine.
Thread Starter
On The Tree
Joined: Sep 2018
Posts: 161
Likes: 4
From: New Zealand
I don't have a press so I guess i'll have to try find someone to do it for me.
Kind of difficult as I live in New Zealand
TECH Junkie
Joined: Dec 2012
Posts: 3,615
Likes: 1,327
From: Iowa
YES it needs to be fixed. Any competent repair shop will have a press. You can use a socket to press the shaft out, with no damage. apply loctite as mentioned above (applying liberally is OK as long as you don't let it "set up" in the feed holes). The shaft has a "double tooth" to locate its position in the drum...so you can't mess up the indexing of it. And it will bottom out very definitively so you don't have to worry about pressing the shaft too shallow.
I've had guys take these to exhaust shops and trade a case of beer for 20 minutes with the press and a can of their brake clean. It's easy.
I've had guys take these to exhaust shops and trade a case of beer for 20 minutes with the press and a can of their brake clean. It's easy.
Thread Starter
On The Tree
Joined: Sep 2018
Posts: 161
Likes: 4
From: New Zealand
Understood, was hoping you would all say 'nah its fine' ah well, better to do it once and do it right (bad cliche i know)
One more question, would the input drum from an early 4L60e work in my '97? Looking at them side by side, they are identical but the side casing one of the holes is a bit bigger? Just curious more than anything.
ah well, better to do it once and do it right (bad cliche i know)One more question, would the input drum from an early 4L60e work in my '97? Looking at them side by side, they are identical but the side casing one of the holes is a bit bigger? Just curious more than anything.
Teching In
Joined: Nov 2016
Posts: 45
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From: New Zealand
Thread Starter
On The Tree
Joined: Sep 2018
Posts: 161
Likes: 4
From: New Zealand
Trending Topics
Thread Starter
On The Tree
Joined: Sep 2018
Posts: 161
Likes: 4
From: New Zealand
Anyone feel like commenting on this article:
https://www.autoserviceprofessional....t-mean-trouble
Obviously I will take the recommendations of the people in this thread over that article, but just curious if anyone has any input/discussions regarding the article, whcih disagrees with your comments.
TIA
https://www.autoserviceprofessional....t-mean-trouble
Obviously I will take the recommendations of the people in this thread over that article, but just curious if anyone has any input/discussions regarding the article, whcih disagrees with your comments.
TIA
Article text incase URL dies:
This bulletin applies to a number of GM light trucks equipped with 4L60E, 4L65E or 4L70E automatic transmissions. Vehicles include 2004-2007 Buick Rainier, 2003-2006 Cadillac Escalade, 2003-2005 Chevy Astro, Blazer and Corvette, 2003-2010 Chevy Avalanche, Express, Suburban and Tahoe, 2003-2004 Chevy S-10, 2003-2007 Chevy Silverado Classic, 2003-2011 Chevy Colorado, 2007-2011 Chevy Silverado, 2003-2004 GMC Sonoma, 2003-2005 GMC Jimmy and Safari, 2003-2006 GMC Sierra Denali, 2003-2007 GMC Sierra Classic, 2003-2009 GMC Envoy, 2003-2010 GMC Savana and Yukon, 2004-2011 GMC Canyon, 2007-2011 GMC Sierra, 2003-2010 Hummer H2, 2006-2010 Hummer H3, 2003-2004 Oldsmobile Bravada and 2004-2006 Pontiac GTO.
Input housing and shaft assemblies from transmissions have been incorrectly considered defective when air bubbles are observed coming from between the input shaft and the housing during an air check.
A small amount of air leaking between the input shaft and housing is not an indicator of a defective part. The press fit between the shaft and housing is designed to contain transmission fluid under pressure but is not air tight.
Do not replace an input shaft and housing assembly solely because of an air leak. Re-use or replace the part based on results of inspection as described in Input Housing and Shaft Assembly Inspection in the service manual.
This bulletin applies to a number of GM light trucks equipped with 4L60E, 4L65E or 4L70E automatic transmissions. Vehicles include 2004-2007 Buick Rainier, 2003-2006 Cadillac Escalade, 2003-2005 Chevy Astro, Blazer and Corvette, 2003-2010 Chevy Avalanche, Express, Suburban and Tahoe, 2003-2004 Chevy S-10, 2003-2007 Chevy Silverado Classic, 2003-2011 Chevy Colorado, 2007-2011 Chevy Silverado, 2003-2004 GMC Sonoma, 2003-2005 GMC Jimmy and Safari, 2003-2006 GMC Sierra Denali, 2003-2007 GMC Sierra Classic, 2003-2009 GMC Envoy, 2003-2010 GMC Savana and Yukon, 2004-2011 GMC Canyon, 2007-2011 GMC Sierra, 2003-2010 Hummer H2, 2006-2010 Hummer H3, 2003-2004 Oldsmobile Bravada and 2004-2006 Pontiac GTO.
Input housing and shaft assemblies from transmissions have been incorrectly considered defective when air bubbles are observed coming from between the input shaft and the housing during an air check.
A small amount of air leaking between the input shaft and housing is not an indicator of a defective part. The press fit between the shaft and housing is designed to contain transmission fluid under pressure but is not air tight.
Do not replace an input shaft and housing assembly solely because of an air leak. Re-use or replace the part based on results of inspection as described in Input Housing and Shaft Assembly Inspection in the service manual.
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TECH Junkie
Joined: May 2012
Posts: 3,050
Likes: 716
From: Poplarville, MS
The third apply oil circuit has so many places that it can leak from that I try to seal up every place that may leak. The 3-4 clutches in my car would only last about a 5,000 to 10,000 miles before going out. The only thing that I did different to get more longevity was to seal up the input shaft to drum leak. Now I only have hard parts brakeage, but the 3-4 clutch wear is good now.
If you decide to press the input shaft out to reseal be sure to support the backside of the input drum in the center where the splines are when pressing the shaft out and back in again. I use a piece of pipe just a little bigger than the shaft and side over the shaft to support the drum when pressing the shaft out. When pressing the shaft back in support the drum in the center where the splines are. If not supported when pressing the shaft in and out the drum may crack.
If you decide to press the input shaft out to reseal be sure to support the backside of the input drum in the center where the splines are when pressing the shaft out and back in again. I use a piece of pipe just a little bigger than the shaft and side over the shaft to support the drum when pressing the shaft out. When pressing the shaft back in support the drum in the center where the splines are. If not supported when pressing the shaft in and out the drum may crack.