Check the teardown video of the Model Y by Sandy Munroe. It clearly shows the cast parts, which now get replaced by a single large part. One can assume, that th

Check the teardown video of the Model Y by Sandy Munroe. It clearly shows the cast parts, which now get replaced by a single large part. One can assume, that they will make similar changes to the Model 3 as soon as the cast machine exceeds the Model Y numbers, as it saves a lot of money in production.