Why are the Grand Central shuttle subway (S train) tracks numbered 1, 3 & 4? Why is there no track 2?

Question

Why are the Grand Central shuttle subway (S train) tracks numbered 1, 3 & 4? Why is there no track 2?

Answer 1

About 20 years ago, the TA (Transit Authority) removed track 2, due to spacing problems at the Times Square end of the Shuttle....that is why when you take the Shuttle from Grand Central, the track 1 platform is so wide.  Originally, back in the 60's, the tracks kept going.  it connected the 4,5, and 6 to the 1, 2, and 3 trains, and would be continuous, without the buffers.  I hope this answer has been helpful to you.  The reason I know this is because I know the former President of the TA.

Answer 2

it must have a historical significance.

do not know but will come back to find the answer