Kenny Coyote
Telly Talk Star
Was that because the actor they had got a better offer or did they think they could find someone better?
It's a shame not to see more of Ackroyd as I liked him a lot
He was doing Little Women. I really liked him as Gary Ewing.David Ackroyd was tied in to something else and so wasn't free for Knots Landing.
It's a shame not to see more of Ackroyd as I liked him a lot. But as it turns out it worked out really well.
Ted Shackelford was the first Gary I saw, and he did a fine job. The first time I saw David Ackroyd as Gary, I didn’t like him that much. But when I watch it now, I think he had more potential than Shackelford. Ackroyd did the brooding/tortured thing very well, and he seemed to have a little more gravitas than Shackelford. He also had great chemistry with Joan Van Ark (but in fairness, Joan had good chemistry with pretty much everyone). I bought Ackroyd more than Shackelford as the sensitive guy who grew up on Southfork (Ted always looked like he just stepped out of the gym or off the beach).
But Ted was good too, and it worked out.

David Ackroyd didn't have the look of a Ewing to me
I always thought Ackroyd did look like a Ewing while Shackelford looks more like a Southworth.Ted's Gary does seem even more like Miss Ellie's son and Bobby's brother, too. He has Bobby's eyes and Miss Ellie's hair and laid back side.
I always thought Ackroyd did look like a Ewing while Shackelford looks more like a Southworth.
They wanted David Ackroyd to commit to 14 episodes (1 of Dallas, 13 of Knots Landing) in late 1979. He was unable to do it because of his involvement in Little Women, so they recast the role of Gary Ewing to Ted Shackelford. Apparently, Joan Van Ark remembered Ted from an episode of Wonder Woman and their chemistry when they appeared together on that, so suggested Ted. David later appeared in a Series 3 episode of Knots Landing, as Karen's first potential love interest after the death of her husband, Sid. David's character spoke with Val on screen, but not with Gary, even though they did appear in the same scene.
I like both men in the role of Gary, but obviously I'm more used to Ted. Ted's Gary does seem even more like Miss Ellie's son and Bobby's brother, too. He has Bobby's eyes and Miss Ellie's hair and laid back side. Ted's chemistry with Joan is so strong, too.