I've notice my front steering knuckle boot is cracked and is leaking grease. Is there aftermarket replacments versus the factor replacement of the entire arm for about $300 each side?
Thanks for everyone's help.

 

Bump
I need help with this also

 

As long as you aren't an X, yes. CZP has them for $45/ea

 

Dealer said I need to replace both front steering knuckles, but can I just replace the ball joint instead of the whole arm?

 

Wait, arm or knuckle ball joint?

If you're talking about the compression rod (aka radius arm; aka front rear control arm), then no the ball joint is irreplaceable and you must get a whole new arm. If this is the case, look on rockauto. They've got plenty of affordable options.

If you're talking about the steering knuckle balljoint, then yes its replaceable, but Infiniti will not sell you just the ball joint. They'll only sell you the whole assembly ($$$)

A few aftermarket companies sell the steering knuckle ball joint by itself. CZP is the cheapest and I've had them on my car for 25k miles and they're all good. Duralast (autozone) also makes them, mevotech (these are cool cuz they have a zerk fitting), and a few others.

 

Sorry. I think it's the steering knuckle ball joint. On the invoice I got, it says both front lower ball joints leaking