Originally Posted by
Johnsmith123
I assume in that case that 1.5 hours should be plenty
Yes; your flight to Australia will start boarding about 45 minutes after you land, which is ample time unless your flight from Canada is late. Your flight to Australia will likely depart from either T4 or TBIT, which are connected airside. It might add another ten minutes if you have to walk from T4 to TBIT.
Originally Posted by
Johnsmith123
On the way home I will be flying from New Zealand to Toronto, with a stop in LAX again for the same amount of time.
I am a Canadian citizen....not sure if I will again clear US Customs in advance in New Zealand, or if I will have to do it at LAX?
Your outbound flight clears US Immigration and Customs in Canada because your departure airport is a U.S. pre-clearance facility. There are no pre-clearance facilities in New Zealand (or Australia, for that matter) so on your inbound flights you will have to clear at LAX. An international to international flight connection at LAX requires a minimum connect time of two hours, so if you only have 1.5 hours, that doesn't sound like a legal connection to me; assuming this is also booked on the same ticket, you should contact the airline and have a lnger connection.