Thanks for your report. It is not possible to know how to reproduce or verify this issue from your description. This could also be the normal / expected behaviour based on the design of your creation. It is very difficult for us to investigate speculative issues but are happy to look at any issue with a clear and simple example.

https://steamcommunity.com/sharedfiles/filedetails/?id=3018446103

I am glad you reply this post, here i posted the said excavator on workshop, feel free to try it. I had made changes to try make the issues goes away, i tried putting the pivot under the turret ring instead of inverted on top of it or putting a "keep alive block" but non is working.

In all the time i am testing, it got 60% chances that the bug appear and excavator soft lock at Robotic pivot maximum angle despite it is unpowered, unchanged gear ratio nor connected to electric, the rest 40% it's working just fine as I want it too, infinity turning, RPS to wheel etc.

https://steamcommunity.com/sharedfiles/filedetails/?id=3018499443

Here is simplified version of excavator, the same bug occur, but on a smaller scale as the mass is lesser.

What does required to reproduce this bug? We can turn left and right with no issues.

Nothing, in all my session, the bug just appeared with no reason with these 2 creations I posted, all other creations working just fine, just the particular layout involving these 2 creations are somehow bugged.

I using all settings including physic on high, and the game is up to date without modded or any sort. I would definitely love to provide anything that would help you guys diagnose if there is any.

https://youtu.be/Q2UMOi4dEcc

I uploaded a private video just to showcase the issue i encountered when the bug appeared, when it;s not, my excavator work fine

Sorry but we need a way to reproduce this issue. Cannot diagnose using a video.