Yes!
When I'm getting stressed out from a conversation going on too long, I start to not be able to find the right words to say, even though normally when I'm feeling rested and relaxed I can actually be fairly articulate given optimal circumstances.
But when stressed, I start to do several things -- I've noticed I begin not to find the right words, I stutter and stammer, I can either start to ramble aimlessly like suddenly my mouth has gone on autopilot and now I'm "talking just to be talking" -- but it's all just repetitive crap going over and over something I've already said.
OR -- I begin to shut down completely and end up not being able to talk at all. That can also begin following the "autopilot" repetitive stage.
If things really get bad and I haven't managed to literally just remove myself from the situation, I start getting physical effects also, such as feeling physically dizzy, faint, the "room starts spinning".
These are in specific, acute situations.
On a long term level I noticed that during the period of time when my marriage was breaking down, which kind of drew out over a couple of years, I was so stressed by my husband and our fights that even when we were not fighting, I developed a stammer. I had never had one before in my life, but I started to have one during that stressful time, even in a normal conversation. He made me nervous and I no longer felt good around him.
I've noticed this starting up again when feeling strain and negativity around a person. I stutter under stress and normally I don't. I'm not sure that's only ASD related though, as I gather than NTs can stutter when stressed too; it's almost a standard joke in sitcoms.