My 2005 RX300 has started to whine from the pulley side of the engine when cold started. It doesn't sound like belt slip - more a bearing noise. The sound disappears after a minute or two and everything else seems fine. Has anyone any experience with this or any ideas what it may be?

 

might be the alternator or a/c clutch. have you tried some belt dressing anyway just to make sure 100% its not the belt?

 

We have an '05 as well. No problem that I know of.

Now, what you described is similar to my '03 Toyota Tundra. For the longest time, I kept thinking it was my power steering going out, but as after changing the belt, it's all fine again. I bought the truck used, and it was 102k when the belt was changed. Depending on miles, changing belt is one of those sooner or later thing anyway, so you may want to give that a try first. BTW, Goodyear Gatorback belts was heavily recommended for the Toyota Tundra over factory by everyone, including a dealer tech. May want to do further research, but it's been good thus far.

 

You may need to replace the belt. As a side note, don't use belt dressing on a serpentine belt it will make matters worse.