Hello,

I have a 2009 Infiniti Qx56 with 89,000 miles on it and the ride is very rough and bumpy. Is this due to the shocks being worn out? When do you replace them?

Thanks for your help !

On newer vehicles I've replaced very few shocks. On pickups the rear shocks need replacing alot it seems. If you load it down alot maybe just try rear ones first.

Other things could be lower profile tires which require higher pressure and have less sidewall flex. Im not sure if this thing is modified in anyway. Make sure you've got tire pressure at what ever the door sticker says. This normally is for ideal ride quality. Obviously more air harder ride. Alot of the quick lubes will just put 50psi in all your tires. This makes it a bit rougher than normal. Although running a higher tire pressure (not exceeding the tire cold limit) ***makes tires last longer in general.

Bumpsteer is what you may be experiencing.

air bags could be shot.
other suspension components could be damaged.

if used, take it to a competent suspension shop and have them smoke over the undercarriage.

Bilstein shocks are the preferred shocks to replace the oem ones.

My own personal experience with my '06 QX56 was when I bought it in Jan '16 it had 110,000 miles on it. There was bump steer (vibration when hitting a bump) and after some investigation found the auto level system wasn't working. Replaced the front struts with Bilstein's (what a dramatic improvement) and replaced a bad relay that operated the air suspension pump for the rear suspension.

I replaced my 2004 QX56 front shocks with Bilstein HD ones when my truck had about 65-70K miles ...big difference. The stock ones suck balls. The rear has the auto leveling system so air bags ...no need to replace those unless they are leaking.

Bilstein shocks are the bees knees! The cats pants! I put them on the 2008 i had in front (had air in back) and they are golden!