Originally Posted by jiejie

1. No change. All CA intl and domestic is in Terminal 3.
2. On a domestic to international, usually yes. Customs clearance is normally at the final exit point in China which would be PEK. You can ask about tagging all the way through to LAX at SZX check-in without having to pick up at PEK, but don't bet on it.
3. Exit Immigration at PEK. Customs likely at PEK, see #2 .
4. I thought the Minimum Connection Time for D > I is 120 minutes so you are slightly less than that. I shouldn't think this is a legal sell if all on one ticket. I'd be loath to try this if it is on two separate tickets. If the incoming domestic flight is on time, you should be able to make it with some hustling, but that's the rub: domestic flights into PEK are often delayed. Check in for intl flights cuts off at T-60 minutes. You could encounter slow queues at Exit Immigration. Finally, US-bound flights will have a secondary security check at the boarding gate. Not a lot of room for error here, but if this is all on one ticket, CA will have to get you to LAX somehow. If you can't change the first segment to something earlier to lengthen that connection time, then be flexible on the LAX arrival end.