4L60E Tranny

I have lost 2nd, 4th, and reverse gears from this tranny and figured that the planitary gear cluster had gone out. Tore the tranny down for repairs and found that all planitaries look as good as the ones that I purchased to replace them with. What am I overlooking?

The transmission has clutches (or bands) to engage the various gears. Since the transmission is open, they are what you need to check. It is also possible that the solenoids are bad.

I have new clutches and plates that I am installing to replace the old ones with, but the old ones look as if they have very little mileage on them. They do have 160,000 on them, but they look to be in very good condition for this many miles. I have burned up a couple of tranny’s and also shreaded a couple, but this one looks great on the inside. I have not been able to find any damage to any of the old parts. I was wondering about the Solenoids, but doesn’t each gear have it’s own solenoid? It is hard for me to comprehend that three of them would go out at the same time. I am stumped on this one and I really would hate to put it all back together with all of these new pieces and it not fix the problem. I need all of the help that I can recieve on this mystery.

The sun shell is broken inside the trans. A very common failure in the 4L60E.

transman

Second to transman618. The sun shell is stripped where it connects to the sun gear. The sun shell will still be attached to the rear sun by the snap rings. This is a weak point of the 700R4/4L60E. If you follow the path of action, the 2/4 band stops the rear sun and the reverse clutch drives the rear sun all through the sun shell.

Here is what to look for. The top photo shows a good sun shell, notice the collar on the top where the 2" hole is. This is where the sun gear goes.

Now, look at the bottom pic, notice the collar missing. Look at the sun gear on top of the shell in the second pic, notice the broken collar on the gear splines. This is where they break. Check yours real good since you have it apart.

transman

Hey, transman, does your significant other mind you having transmission parts in the kitchen?

SHHHHHH Dont tell her, she’ll kill me… She was sleeping… LOL

transman

THANK YOU transman.

I was so worried about getting this unit put back together and finding that I had not fixed the problem, then having to pull it again. After I looked at your post, I went to the shop the next morning and looked at my sun shell and that was when I noticed that it had no teeth on it. I was getting so upset with this unit since I did not have a lot of metal shavings in the pan and all of the planetary gears looked as good as the ones that I had purchased to replace them with. Me and my dad both could not find any damage to the gears or to the case and we both were stumped on this tranny. Neither one of us looked at this shell when we removed it from the case. But after this post, I went back and looked at it again and could see where teeth used to be. Needless to say, it is almost smooth now.

Thank you again, you saved me from thinking that I was losing it and in my faith in the help from others.

ledjr857

Absolutely… Glad to help. You would not believe how common this problem is in the 4L60E transmission. Did you get it on the road yet???

transman

not at the moment, will be rolling again this saturday. Can’t wait either, miss driving it.

One quick query. Were the teeth torn from the inside of the flange with the flange still attached to the shell as on transman618’s upper photo or was the flange torn from the shell and still attached to the sun gear as on transman618’s lower photo.

Curious TNX

The teeth were gone from the flange, the flange is still attached. This is one of the reasons that I overlooked this piece for damage. I just knew that the planetary gear was shreaded like in the 700R4 that I rebuilt years ago.

ledjr857