X Fusion Sweeps about two years old. Started sounding a bit squishy so I did a lowers service, new oil, new SKF seals (green if it matters) and foam rings, all from J-Tech so I assume decent enough even though not the XF N-Volve or whatever they are called seals. Correct quantity of oil put back in. Now when I lift the front wheel there is an ‘air moving’ kind of noise as the sag extends, and the squishy noise is still there when I bounce them hard. What’s going on?

Ahem…

I get similar on my Pikes when the rebound is on slow

As hainman alluded to it could be the damper.
Changing the oil in that should be ok I did my slant fork and don’t remember any dramas.
MTBR RL2 thread has pictures and all the technical detail you need.

Thanks, I’ll try that then. Just did the lowers and never went near the damper.