Does LEGO mix old and new pieces?

StudioVII

I was building a kit and noticed that the jumper plates 3794a and 3794b were mixed together, the latter having a slight groove at the bottom while the other did not. Also, some pieces the LEGO logo on the brick wasn't as pronounced as on others. Is this normal of LEGO to mix old and new batches of bricks in their sets? Iv'e never really paid attention to this and just noticed it. 

klinton

Yup. It happens on occasion. Your set was packed between production runs.

The_Rancor

Similar thing often seems to happen with 1 stud wide tiles of various lengths - some have a slight opening in the dots underneath, and some don't - in the same set. I feel like something similar happened with clips when they were upgraded to the modern version too.

I was building the recent System scale Sandcrawler the other day and discovered that the 1x2 and 1x3 tiles differed slightly with their Mould marks - naturally I had to ensure they were identical on both sides for symmetry!

Bumblepants

I got my Fire Brigade at the very end of it's lifespan and it had the modern tool set inside the small polybag with the tire iron etc. Meanwhile the directions indicated it should have the older 6 part tool set from the plastic wheel sprue.

Baby_Yoda

I got #10243 Parisian Restaurant at the start of this year and the jumper plates were inconsistent. Unfortunately, the disparity is quite obvious. I just grouped plates of a kind together so the difference wasn't noticeable.

gmonkey76

And let's not forget the UCS Stardestroyer some sets came with lt. gray and li. blueish gray parts.

Baby_Yoda

Same problem with the early Imperial Star Destroyer, I think.