PETE!
Shhhh.
Bec what Pete is trying to say is that the 'springs' themselves won't be under warranty, because they aren't Toyota. The springs themselves will have their own warranty anyway. If you get a decent brand like Lovells, Kings, Tein, D2 or TRD then you'll have no issues. Check with your service centre just to let them know you'll be changing them. If they say that the springs will void the warranty on the entire car then you ask for it in writing and tell them you'll contact the Toyota Head Office. It's bullcrap. Doesn't void your entire warranty. 2 dealers here in Canberra said that they couldn't give 2 hoots what I did as long is it was legal, installed by a professional and didn't create problems for the Toytoa Genuine parts.
Some a'hole dealers can pick on something like a CAI (Jase) and blame it for problems in the car, however, springs are fine. They effect nothing bar the ride height and the wearing on the shocks.
If you want to lower just go 35mm. Your stock shocks won't wear out as fast and it'll be better for you in Sydney w. the bumpy roads.
Sorry for ranting lmao
PS: Hey Pete *slap* lol