We just picked up our new 2012 ST25RB on Feb 11, and slide does make a noticeable whining sound just before slide begins to move. I've read few postswhere members also commented on these sounds.......I believe its normal. How do you like the trailer? We love ours. Only comment against ST25RB is the lack of a heating vent in the bathroom, which would keep bathroom warm & cosy on those cool evenings without having to leave bathroom door open for heat to get in.
Happy trailering!