As you all know Lockdown first appeared in Transformers Animated voiced by Lance Henriksen, serving as the character's original voice.
Lockdown has also been the first of any decepticon that operates solo other than Starscream, and makes deals with decepticons like Megatron and Blitzwing, even the autobots. Even though Lance voiced Lockdown it would be too much of a coincidence for him to be voicing the character again so it maybe someone else that Bay would cast to voice the villain. Some of you are expecting someone with a bold voice or an elderly voice that would fit the character's voice in the film but sometimes it doesn't work that way. If Lockdown appears in the film Bay would cast someone with a foreign toned accent and it maybe someone under the age of 50. Fortunately there is on actor familiar enough to voice Lockdown and believe me, he was the menacing villain from Iron Man 3, who yes that the producer Kevin Feige ripped everyone off with over various reasons;
Guy Pearce
Surely Guy Pearce was the actor that ruined Mandarin for everyone in Iron Man 3 but that is not why he would be expected to voice the decepticon Lockdown for the fourth Transformers film. It is seriously the opposite reason; meaning that because of how bad ass he was as the crazy maniac Aldrich Killian alias MODOK alias Firebrand and with that Austrailian tone of accent I'd say he would really fit the voice of Lockdown's Transformers Cinematic version.
After all, Guy Pearce hasn't done any voice actors since he started acting since the late 1980's and because of his role in Iron Man 3 as a bad ass super villain, I say it's time for the actor to start embarking on voice overs and it would be a cool oppertunity if Bay can cast him as Lockdown. His tone of voice would be cool so lets hope Bay gives it to him and I say we should tell him ASAP. SOme of you would say we don't want him voicing TF 4 Lockdown but after that blowback that the actor, director and producer have caused in Iron Man 3, you can't always get what you want, can you?
Transformers 4 is set to come to theaters next year and if Bay gets more vehicles on set for decepticons like sports cars for the stunticons, it will be a blast!