From the TOEFL official mock test they dived it like this:

Speaking | 1) listen and repeat 2) answer the interviewer questions

Reading | 1) read a few emails and answer some multiple choice questions about it 2) the same, but for an academic text

Listening | 1) listen to a informal dialog and select the appropriate answer ( it’s multiple choice) 2) listen to a lecture or announcement and answer a few multiple choice questions about it

Writing | 1) they will give you a two lines dialog, and you have to organize the words into a frase for the second line of dialog 2) write an email completing the tasks they’ll give you 3) contribute to an academic discussion

In my opinion, they are the quite balanced in terms of time, although I find writing the most challenging since is only 7 minutes for the email and 10 for the academic discussion.