The AHC system does not "recirculate" fluid, so you will still have old fluid in all of the components that actually use it.I’m curious. Why not just suck the fluid out of the reservoir and swap with clean fluid? I know its a shortcut, but if it remove 90% of the old fluid, wouldn’t that be good?
I know this doesn’t help op, but I’m thinking of servicing mine at 75k.
OP, is Lexus going to cover the pump?