This is sad and ridiculous. (Copy from your other thread posted above.)
The shop filling your FUD. Fear, Uncertaintay, and Doubt. That's what they do, and you just have to look at their estimate to verify what I am saying 50% of the time.
The other 50% of the time they are right.
First, there is nothing special about your Infiniti. It's really built very basic. But like BMW they alway quote too much and leave you to think the sky is falling so they can rake in the big bucks.
In this case, I bet you can fix your problem one of several ways:
1) Go "Hillbilly"... If you have not yet flushed out your power steering reservoir do so. There is several ways to do this. With two people, you can purge old fluild by disconnecting the return like at the reservoir and drain into a catch-can. Then start the engine and let the pump enpty the old fluid into the catch-can while you poor fresh fluid into the system... mixed with a bottle of Lucas Power Steering Fix. Note: If you see fluil leaking out of your rack-and-pinion power steering arm, then use Lucas Power Steering with Stop Leak. (Or whatever they are calling it these days.)
80% if the time this will fix all your noise and leaks.
Note: If you have some steering slop in the wheel, you can fix this by tightening the adjustment bolt +1/8 turn on the rack and pinion from under you car -- after you remove the oil skid cover -- or not. I can't remember if this is necessary.
Note: It's also easy to replace your rack and pinion bushings. (See YouTube on this.) And by doing so this will fix andy wheel bounce you may have when you tires bounce over bumps in the road. And FYI, don't let any mechanic tell you you need to remove the rack-and-pinion to replace these bushings. I.e., they are not press fit!
Note: Once you learn how to purge your old power steering oil, at 100K miles, it's time to purge your transmission fluid the same way and avoid the WRONG way of doing it the dealer/stealer or other shop who uses a vacuum pump. This is dangerous for cars with lots of miles, but it is SUPER IMPORTANT to do. (Do a seach on this forum for tips on how to do this by searching my other posts.)
Lastly, Infiniti quoted me $450 to replace the cheap transfer case fluids, and differential fluid, whick is nothing more than pulling the drain plug and refilling just like any other oil change. However, they love to over-bill.
Infiniti makes a high quality produce that CAN BE easy to maintain, or at least as easy to maintain as any other car. Your Stealer just wants you to think you are driving a Japanese-Mercedes.
There is also no reason a transfer case should have problems at 100,000 miles. However, since it took 10+ years to put 100,000 miles onl your car (15+ in other cases) then why not change the oil now!
By now, I'm guessing the OP paid the mechanic, so do-tell-us what the fix was?