Hi, I'm about to do a big maintenance on my G37S coupe, transmission, rear diff, power steering, And since I'll go under the car, I wanted to know, if there is any maintenance for the rear All wheel steering system, if yes what ? Like oil ? or other stuff to check. I would guess it's the same fluid as the power steering but if anyone have more info on the maintenance, please let me know.

Thank you

 

The 4WAS system in these cars have a completely sealed, electromechanical actuator for the rear wheels. There is no maintenance required for the rear unit. As long as everything is tight and there are no obvious signs of a problem, just leave it alone!

I would suggest you download section STC (Steering Control Sytem) of the Factory Shop Manual from here as this will tell you everything you ever wanted to know about the 4WAS system.

 

Thank you very much. I'm taking a look at it.

 

Like ILM stated before this is a sealed unit that's greased up. The rear rack doesn't move as much as the front which is why it can be electrical.
With that being said, common failure items are rubber components.
The rack uses rubber bushings that can crap out with oil leaks coming from the front along with the rubber bushings in the lower control arms that is what the rack uses to adjust.

According to an Australian enthusiast here he went with solid bars and bushings in his rack and per his experience it improves the predictability of the system.

I have not had any issues with mines so far.

 

Thank you