My 2012 G37x’s steering wheel shakes at highway speeds (not death wobble but also not slight vibration) only happens at 65+ and does seem to get any worse(or better) over 80. tires were aligned and balanced and the issue still persisted. Power steering fluid is between the min and max but hasn’t been changed recently ( to my knowledge)

as a side note but potentially related my brake light will occasionally flash on while accelerating from anywhere under 30 to anywhere over 40. But it does not happen everytime

any shared experiences or knowledge on how to fix would be greatly appreciated!

 

How many miles are on the car? If it’s higher mileage it could have something to do with the condition of your suspension bushings, ball joints, etc.

 

Might wanna try road force balancing. And can we assume you already checked the fluid level?

 

Car has ~140,000 I’m the second owner bought at 135,000 most the miles are highway. Fluid levels are all ok but I will definitely be flushing them soon


just jacked the car up today and at least to my untrained eyes the control arms appeared to be in ok
zero play in the front wheel bearings

only thing that really caught my eye was the crossbeam not being in the greatest of condition (pictures attached) other than that I haven’t had too much time to go super in depth. Will look into road test balance
Nissan supposedly balanced the wheels when I brought it in for an alignment and inspection

brake rotors are clearly aged but don’t have any obvious signs of warping or heavy wear

Passenger side

Driver side

 

Check to see if the yellow or dot on the tire is right next to the valve stem. Many installers ignore this and just mount the tire any old way, and if they don't match the lightest tire point (yellow dot) with the heaviest wheel point (valve stem/TPMS) it takes extra weight to balance and may not balance perfectly at all.