Couple pesky, little (or maybe not so little) issues:

On a cold start, when I back out of the garage and shift to drive, I get a groan in the rear. Lasts maybe two or three more shifts from reverse to D, and then goes completely away. Diff fluid was changed four years ago. What is this and why on a cold start only?

No. 2, lights for the passenger side front door do not light for the window switch. Changed switch, still no lights. On rear right pass door neither switch nor puddle lamp lights. Rear left pass door puddle lights but not the window switch. Besides pin testing all the wires, is there a well known culprit for these power switch lights?

Finally, for exterior scrub -- has anyone tried 3M's Hand polish glaze? Other 3M products used in conjunction with it?

Thanks!