Hello everyone,
I have tried to search this issue but have come up short. 4l60e, Low Reverse Piston. What appears to be the sealing surfaces inside the case for this piston have vertical grooves and gouges. This is 3 for 3 cases that I have noticed this same deal. Is this just not a common thing or is it not really an issue to worry about? Thank you

 

How many words is a picture worth again?

 

Yes a photo would help alot, markings in case from piston running up and down are common . But to say for sure need to see .

 

 

Each one of these vertical marks is rough enough to catch your fingernail

 

This area is pretty forgiving if you can scotch brite them smooth probably ok , Its only applied in reverse at high pressure, Of course I can't say for sure without feeling them. Look like may have had a planetary failure and some metal got in there at some point, It's really judgement call that can't be made via the internet.

 

Cool, I was wondering if it could be sanded and smoothed out but I have not moved forward without a second opinion. I have three cases that I picked up as cores with the same issue. Try one and see I reckon. Thank you.

 

Like I said common to see and unless pretty deep usually not an issue the square ring back there leaks. pretty somewhat anyway , I would clean up with scotch bright as smoothe as possible and go with it like i said unless real deep but that is a call you will have to make .
More than likely will be ok.

 

For the cost and abundance of cases, if this were anything for a customer, I'd just be grabbing a new case.
If this is your personal vehicle and you don't mind a small risk then you can likely clean it up and run it.