No, he didn't. During the primaries, he would say he admires Cruz and then spend the next 2.9 hours speaking about Trump in glowing terms.
I remember when a woman called into his show during the primary and said that if Trump was the nominee, she could not in good conscience vote for Trump and would go third party - and Rush said plain as day : "Then you are voting for Hillary" - upon which I immediately turned off his show and never again put it on after decades of being a loyal listener.
But I saw the handwriting on the wall. I had cancelled my 24/7 membership about a month prior to that call, and after I heard that - I was done with him period.
Limbaugh is a party loyalist before he has fealty to the principles he paid lip service to all those years apparently.
In fact, they all do. Levin was the last one I held onto listening to, and finally couldn't when he too revealed he was all talk after repeatedly warning the GOP he was an inch from leaving their party - only to insist all of us vote for them and for Trump.
I can say that I feel a whole lot better having given talk radio the heave-to, and the only time I get my blood pressure up is when I have to read all the stupidity rather than hearing a steady diet of it 6 or more hours a day.