Re: AQ125A w/ 270 outdrive makes noises when the steering wheel is turn all the way.
Noise when turning, is quite common on the older aquamatic drives. Especially those that have coarse splines, where the driveshaft is connected to the U-joint. As far as I know, Volvo changed the splines from coarse to fine in approx 1985. That cured some of the growling noise.
I've had a 290 drive with fine splines, and compared to a 280 drive on a friends boat, the 290 was much more quiet when turning.
Off course, if the U joints are worn, it will make more noise than normal.