This is one of the many questions which paleontologists tried to find an answer.
First of all : who is Sue?
She is the "largest" tyrannosaurus known and she was discovered in the summer of 1990. It's the most famous trex and the most complete, she stays at the Field science museum in Chicago and it's the t rex who gave inspiration to the famous film "jurassic park".
She is 12.3 meters long and almost 4 meters tall, she is larger than the largest complete giganotosaurus ever found ( holotype/type) too by recent discoveries.
Sue is also considered to be a record for a tyrannosaurus's size, however new evidence has come to show that she isn't the largest tyrannosaurus, just the most complete.
The specimens supposed to be larger than her are in total 3 , one is called MOR 008 or "trix".
This giant after have been discovered was fought to be larger than Sue , but experts disproved that, it is slightly smaller than Sue.
Another one, is just based on a small jaw fragment , considered to be "larger" than Sue's one. Well, I personally think that just a jaw fragment can't prove that it is bigger, we need a full skeleton to prove that.
Now we have the last one, the great point.
"Celeste" or Ucmp 137538 which we have a full large skull
This is the largest tyrannosaurus skull ever found in the history of paleontology and probably the biggest .
Celeste is less fragmentary than most of the other tyrannosaurus specimens estimated and less than the giganotosaurus paratype one (I will talk about it on another topic don't worry;)
It's skull is some centimeters longer than Sue's one and it weighs some kgs more , by the size it is estimated to be 14 meters long ( 50 ft) someone say that it is larger than Sue , well it could be around the same size but it is WAY heavier and larger than giganotosaurus holotype for sure just like sue.
As conclusion, I suggest to you all to do not believe 100% these estimations, these are just estimations and opinions, they could be right as they could be wrong.
Comment below of what you think about this and share your opinion if you want :)
In nature, or you kill...or you get killed -Jack London