ZF lifeguard 6 WAS an aftermarket fluid "authorised" by ZF (the autorized list which has since been revoked) not sure if this one is as bad as Transmax but there has to be a reason why the genuine fluid cost 2X more than the others, you get what you pay for. I rather be scared about using an aftermarket fluid than being scared of having to replace the gearbox.....again..... BTW I did check out the filter locations and the filter openings on both the steel pan and the plastic pan and they are INDEED slightly different in design But whatever you do, its up to you, the safest (but costly) way or cheaper (but fear of the unknown)