whine possibly from gear box

hi ive just bought my first jimney a automatic 2015 with 27000 miles being my first jimney im not aware of any running noises they might have 
so my question is do they make a sort of whining noise when underway

Not loudly.

The transfer box chain "sings". If someone has fitted a skid plate it reflects the sound back up into the cabin (guess how I know   )
Autos do whir a little but not really loud enough to notice. The axle can whine a little, and the tyres can be quite loud.

They are not quiet cars tbh, if you are used to a luxury car with some "insulation" it may sound odd.

Maybe someone is close to you and can have a listen.

Agreed they're not a Bentley for sure but the automatic is noticeably quieter than the manual mostly because the revs are lower for any given speed. Where in the world are you that one of us may be able to listen to it for you or give you a baseline in ours?

I've owned two automatics (05 and 07) and yes, the transmission has a certain whine or hum to it that I believe is normal. They both did / do it in the exact same way. It's not an ugly sound, I actually quite like it. Happens the second you put your foot down and stops as soon as you lift it.

The properly "bad" car sounds are normally quite overtly nasty sounding. If you're getting crunches on gear shifts or something then I'd worry about that. A light hum is fine, so long as it isn't getting worse / louder over the next e.g. 6 months.

its coming from the diffs (front and rear) and also from the transfer case, be advised there will be a chain slap noise (crunching sound) from the transfer case if u start the car on the hill, most suzuki dealer knew about this design flaw and i just try to live with the sound, although theoretically it could be an easy fix with a tensioner ?

The manuals have a bit of a whine at 70mph, should you choose to crank one up that high.  Smooth enough, though.