4L60E pan drop and filter change pics and filter o ring carnage

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Jul 14, 2020
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Decided to try to get my transmission pan replacement done today (replacing with an aftermarket SKP with a drain plug). I'm regretting trying to do it so late in the day as it got dark very fast and things didn't go well with the filter o ring. I'm wishing I just left the old one in now. It was extremely tight and difficult to pry out and I have gouged the aluminum around the edge where it goes in. Trying to hammer it in with a 19mm socket backwards on an extension but it would not stay straight in the bore and ended up getting bent. Now I'm picking up a new filter kit in the am to try again. Any advice?
I am also installing an inline filter kit so leakage past the internal filter because of the gouges hopefully won't be as big of a deal. I just need to get a seal back in there so I can install the new filter.

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The gouges could be an issue if they're deeper but very likely not. Check its fully warmed up operation nonetheless. If you have slow engagement, odd acceleration, or slips it could have caused the pressure to drop but I think that'll be fine. Didn't go deep but still be aware.
 
Looks like you damaged the case a good bit, that could cause air to slip by and aerate the transmission fluid and loss of pressure resulting in failure.

99% of the time the original seal is perfectly fine and if you are not familiar with removing and replacing these seals it is best to leave the original.
 
The gouges could be an issue if they're deeper but very likely not. Check its fully warmed up operation nonetheless. If you have slow engagement, odd acceleration, or slips it could have caused the pressure to drop but I think that'll be fine. Didn't go deep but still be aware.
I'm under the impression that the leaks will only allow fluid to bypass the filter. Are you sure it could cause a pressure loss?
I'm still worried about how the gouges might be preventing getting the seal back in. I have a friend stopping by tomorrow morning who's actually a retired licensed mechanic so hopefully he can help coach me through this.
I will be installing the inline filter kit at the external trans tomorrow night. I need to get this back together tomorrow morning as I already have my dad's trailer attached to go pick up some scrap metal.
Also going an hour north to pickup my new parts truck 02 Sierra 5.3 4x4. I will now have a spare 4L60E if things go bad but the pan magnet looks pretty good for 60k miles since I last dropped it and did this. Currently at 266k miles.
 
Looks like you damaged the case a good bit, that could cause air to slip by and aerate the transmission fluid and loss of pressure resulting in failure.

99% of the time the original seal is perfectly fine and if you are not familiar with removing and replacing these seals it is best to leave the original.
I managed to replace it last time without nearly as much trouble but it seems like the new seal that went in last time was a tighter fit.
But I agree that I should not have bothered to try to replace it.
 
I managed to replace it last time without nearly as much trouble but it seems like the new seal that went in last time was a tighter fit.
But I agree that I should not have bothered to try to replace it.
My suggestion make sure the surface further in is not gouged and if you noticed any weird behavior that is a bad sign, also if you drive a bit and pull the dipstick and notice the transmission fluid look bubbly on the dipstick and the transmission is properly filled that is a sign of aeration.
 
If the oil level above the gouge marks it should not have a pressure loss. If the oil level ever gets below the gouge marks where air could go through then it could cause operation issues from pressure loss and aeration. I don't know for certain where the oil level should be since I didn't check to see where the dip stick lines level at with it still inserted when i took my pan off.
 
I'm under the impression that the leaks will only allow fluid to bypass the filter. Are you sure it could cause a pressure loss?
I'm still worried about how the gouges might be preventing getting the seal back in. I have a friend stopping by tomorrow morning who's actually a retired licensed mechanic so hopefully he can help coach me through this.
I will be installing the inline filter kit at the external trans tomorrow night. I need to get this back together tomorrow morning as I already have my dad's trailer attached to go pick up some scrap metal.
Also going an hour north to pickup my new parts truck 02 Sierra 5.3 4x4. I will now have a spare 4L60E if things go bad but the pan magnet looks pretty good for 60k miles since I last dropped it and did this. Currently at 266k miles.
If the minimum operating oil level is above the gouge marks it should not have a pressure loss. If the oil level ever gets below the gouge marks where air could go through then it could cause operation issues from immediate pressure loss and aeration after a while. I don't know for certain where the oil level should be since I didn't check to see where the dip stick lines level at with it still inserted when I take my pan off. But if the gouge marks aren't deep into the interior diameter of the seal hole it should be fine.
 
Yeah I think it'd be good to do something to make sure it seals good like taking it out and gluing it in as BrendanC suggests.

Maybe wait to suggest that to the mechanic you have coming tomorrow.
 
If the minimum operating oil level is above the gouge marks it should not have a pressure loss. If the oil level ever gets below the gouge marks where air could go through then it could cause operation issues from immediate pressure loss and aeration after a while. I don't know for certain where the oil level should be since I didn't check to see where the dip stick lines level at with it still inserted when I take my pan off. But if the gouge marks aren't deep into the interior diameter of the seal hole it should be fine.
In the morning I will check how far up the dipstick the full level is and then measure up from the bottom of the dipstick. I think this should be below that level. And I'm pretty good about checking the level and making sure it's right at full or slightly above.
 
In the morning can you also inspect to see if any damage went beyond just the outer surface of the hole which isn't a big deal. Any lines even fine ones in the ID of the hole are notable.
 
i would pull that back out and glue a new one in. aeration before the pump will kill it.
What would be a good product to glue it with? The picture is with the old one still installed. Sorry I didn't mention I didn't get a picture of after removal. There are small gouges all around the edge where the o ring goes up into...but I have to get a new one tomorrow and attempt reinstall.
 
In the morning can you also inspect to see if any damage went beyond just the outer surface of the hole which isn't a big deal. Any lines even fine ones in the ID of the hole are notable.
I will check that also.
 
What would be a good product to glue it with? The picture is with the old one still installed. Sorry I didn't mention I didn't get a picture of after removal. There are small gouges all around the edge where the o ring goes up into...but I have to get a new one tomorrow and attempt reinstall.
a very VERY thin layer of silicone or preferable loctite sleeve retaining compound. this small gouges will cause leaks. it is better to not mess with those seals.
 
There is no reason it should be anymore difficult to drain and fill an automatic transmission, than it is to change engine oil and a filter. On some of these things it's absolutely ridiculous what you have to go through.

Being forced to replace pans. No drain plugs. No dipstick. Complete nonsense on determining how much to refill. Temperature critical. And on and on. These engineers today could over complicate a cup of coffee.... 350 Rocket you have my sympathy.
 
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I wonder if a non-setting gasket compound like Hylomar would work in that situation.

Your photos make me glad I left the factory seal when I changed my 4L60E filter!
 
@350Rocket: I feel your pain, brother. Changed the fluid and filter in a 2001 GMC Safari (same transmission as yours) and messed up that seal but good. My mechanic friend who bailed me out showed me the tool he uses for those seals...IIRC (was many years ago) it looked sorta like a miniature axle bearing puller. Learned my lesson that day...😳
 
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