We have finally had some clear skies downunder to use my new AP1600 delivered a few months ago. I have noticed some slews are very noisy, particularly in the RA, but also Dec gearboxes. Noise is high pitch and varies in frequency, almost sounds like the motor is about to stall. Other Slews are very smooth and the noise very consistent. Mount is well balance and scope weighs 30kg, slew speed 600X. Temp is16 degrees Celcius. Is this normal? Thanks

Hi Luke,
I noticed my 3-year old AP1600 had a noise issue a few months ago. It happened in both RA and Dec but in random fashion.
Consulting with George@AP, I got the advice and conducted the slew speed set to 600x and the re-greasing for RA and Dec gearboxes, which perfectly resolved the issue.

> In cold weather the mount should be slewed at 600x.    You made need to do an adjustment of the Backstop (while in Park 3 and the power off).  
> https://astro-physics.info/tech_support/mounts/1600gto/1600gto-auto-adjusting-gearbox.pdf
> Greasing should be done every few years under normal usage.