4L60E Information Thread

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Scooterwrench

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@NickTransmissions
If you saw this what would recommend?
There is a welch plug that is pressed into the end of those slip yokes. Apparently yours is leaking. You may try to seal it by cleaning it well with carb cleaner making sure you get it completely de-oiled and smearing ultra grey silicone sealer around the perimeter of that plug. If it's a daily driver then do it in the evening so it has all night for the silicone to cure. There's a good chance you may need to pull the driveshaft so you can flex the joint to get in there to clean and seal it.
 

SUBURBAN5

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There is a welch plug that is pressed into the end of those slip yokes. Apparently yours is leaking. You may try to seal it by cleaning it well with carb cleaner making sure you get it completely de-oiled and smearing ultra grey silicone sealer around the perimeter of that plug. If it's a daily driver then do it in the evening so it has all night for the silicone to cure. There's a good chance you may need to pull the driveshaft so you can flex the joint to get in there to clean and seal it.
I thought the output shaft seal was bad. But seen a lot of mixed info on silicone. I thought by plugging the hole, you'll cause damage?
 

SUBURBAN5

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It's dry around the output shaft seal.
I'm referring to the internal output shaft seal.
I thought the output shaft seal was bad. But seen a lot of mixed info on silicone. I thought by plugging the hole, you'll cause damage?
Yes trans rebuilt and that's what they did. Me being a over thinking pain in the ass felt like they were being lazy not to replace the internal seal. I replaced the yoke way before the trans rebuild and never had an issue. Now 1 week after the rebuild its leaking. Knowing how lazy people are they most likely didn't replace the seal to begin with.
I just figured there's a hole there for a reason and by plugging it would cause some type of long term damage or something. Btw the original yoke had a hole as well. Truck a 98 c1500 burb
 

Scooterwrench

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Sounds like you got the problem diagnosed. I would be taking it back down there and having them finish the job.
Yes,if it has the internal sleeve seal then it needs a vent in the yoke.
 

Sideburnz

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My name is Johnny, I own a 1999 Chevy Tahoe 2DR/2WD 5.7/4L65e. Starting about a week ago the Tahoe started slipping when it shifted into 4th gear going down the interstate. Stopped as soon as I could, checked the fluid and added 1 quart. Got back on the interstate and it did fine the rest of the way home (about 5 miles).

Got in it to run errands a couple days ago and it still ran great. Made a stop then got back on the highway and discovered that it only had 1st-2nd gear, no 3rd or 4th even when manually shifting. Took it back home.

Today: First test run the Tahoe had 1st-2nd gear only no 3rd-4th even while manual shifting. Second test run the Tahoe shifted perfectly though all 4 gears no problem. I decide to take the Tahoe into town to get some fuel once agian shifted perfectly though all gears. After getting fuel the damn thing did it agian 1st-2nd gear only, no 3rd or 4th. (All these trips had maybe 5-10 minutes betwwen each of them.)

Reverse works fine no problem. I've read though countless forums and everthing is pointing to the input sprag but with it being random I'm not for vfor certain. Thinking I'm going to be looking at a full rebuild. Please let me know your opion on what it's doing.

Thank You
 

NickTransmissions

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Reverse works fine no problem. I've read though countless forums and everthing is pointing to the input sprag but with it being random I'm not for vfor certain. Thinking I'm going to be looking at a full rebuild. Please let me know your opion on what it's doing.

Thank You
Johnny, your 3-4 clutch pack is likely shot; if it was input sprag, you'd have no movement in D,D3 only in manual 2 and low (1). The input sprag gets replace on overhaul so it doesnt fail shortly afterwards.

Will you be rebuilding it yourself?
 

Sideburnz

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I really want too! I've turned the wrenches on my own cars for years even built one of the fast 5.7 TPI motors around but I've always had reservations when it comes to breaking open a transmission case. The guys that I learned my wrench skills from lead me to believed that it was some kind of crazy voodoo inside those cases.
Since you'll be working on a 4L60E, you won't need to spend a ton of money on specialized tooling as these transmissions only need a few things...I'll film a 700R4 and 4L60E special tools video today or tomorrow and post the link here so you can see everything you will need, how it's used and appx costs/places to acquire.
Plus I'd need to get the tools you've listed. In #63 you mentioned doing a tool video did you ever get that accomplished? I'm in the process of watching your videos now.
 
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