Last week I had three transmissions come in on the same day, all with shredded planetary gears from the same 4L60E batch.

Has anyone else run into a bad run of GM transmissions from late 2019, because I spent four hours pulling metal out of a valve body on the third one and I'm starting to wonder if it's a pattern.

2 comments

2 Comments

lisak261mo ago

Did you end up checking the build date stamp on the bellhousing before tearing into the others? @margaretm23 I started doing the same thing after my second one. What finally worked for me was treating every 4L60E from that late 2019 range like it was a time bomb. I'd pop the pan off first and look for that telltale glitter before pulling the whole unit. Saved me a ton of hours, and honestly, I just started swapping the whole planet assembly out as a precaution if the fluid looked even a little sparkly. The upside is you get real good at those rebuilds real fast.

margaretm231mo ago

Oh man, I used to think those 4L60E horror stories were overblown until I got three from a late 2019 batch myself. First one I figured was a fluke, just bad luck. But when the second and third both had the same shredded planetaries and metal flakes in every nook of the valve body, I started feeling like a fool. I spent a whole Saturday fishing tiny metal shavings out of a separator plate with a magnet, and that's when I knew something was off. Now I check any transmission from that era for the build date before I even crack it open.