Ok I know this is an old thread but i'm hoping someone can respond soon..

Flying in from amsterdam (KLM) to JFK. then I only have 1 hour 30 minutes to switch to a Delta flight to LAX. (Assuming KLM flight is on time). Delta is I think at T4 and i'm arriving at T2 (or vice versa).

So my question is.
1 hour 30 mins enough to clear customs, get bags, drop bags off again, use airtrain to switch terminals, go through security again and board?

Delta have assured me an hour is enough. Posts here suggest otherwise!
I'm a British citizen.

Thanks for your help!