I first noticed this issue after reaching around 5,000 miles in the 18 SV. Any sharp left turn (u-turn) on a flat or downward include would cause an audible creaking sound coming from the left front area behind the dash.
First visit to original dealer resulted in "unable to replicate." Took to 2nd dealer a couple weeks later and was easily replicated. Tech investigated it for at least 2 hours and could not confirm the location. Weeks later Nissan regional tech lead worked with on-site tech and attached wireless sound sensors to multiple areas.
Confirmed it was not the axle, not the wheel, not the brakes, not the CV joint, and most interesting it was NOT the strut tower (older LEAFs has a TSB for strut tower spacers to solve a similar sound.)
After spending another 4 hours taking apart the under side panels and other components, the going theory it's a bad weld somewhere in the chassis. This will require me to leave the car with a certified body shop that will have to disassemble much of the left side to get to the chassis defect.
Dreading they won't be able to put it all back together correctly but we'll see. Warranty issue means I get free rental (dreading a ICE car too).
What's disturbing is I have another 18 MY SL and it's starting to exhibit the identical sound...
2018 SL - In Service 2019 JUN - 2020 APR 94.3 SOH
2018 SV - In Service 2019 JAN - 2020 APR 92.0 SOH
2013 SL - In Service 2013 FEB, Sold 2018 JUN (50,050 mi) - 4 Bars Lost (44,255 mi)
Location: Raleigh, NC