I jacked up my car, and found that the two front tires have about 1" to 2" different distance from the ground. Is this a suspension problem? Should I send my car to dealer for inspection? Many thanks.

 

At which state? While's the car's jacked up? Or back on the ground? Suspension might take some time to settle.

 

I jacked up my car to change oil in my garage. Before that, I heated my car for few miles.

 

So you are seeing a difference in height while the car is jacked up? Need more info:

1. How did you jack up the car?
2. How old is your car?

 

I used a floor jack to lift my 2012 RX up.

 

One side at a time, right? This is not a good way to determine the unevenness of your suspensions. Does the car look even when it's on the ground? If so then you should have nothing to worry about.

 

I actually put the floor jack on the front center to list the car, both front wheels up at the same time. The different height of the wheels was noticed when I put the jack stands.

The car seems to look even on the ground, but I did not pay special attention to that though. I probably will do it tonight.

 

Ride height is the best way to determine if the suspension components - springs- are not sagging.
Each side of the car may have a different coil on the strut depending on load in that corner.
Unloaded, they may display differently.
Chassis Manual, not sure if available for this car, will give you hard measurements from the ground to a given point on the fender or rocker panel.

Replaced all 4 coils on my old Buick a few years ago............can get very confusing.
AC, no AC, engine size, transmission size, HD or regular duty..........etc..
17 different coil springs were available on that car as new depending on options.

 

This is a non-problem. Most cars do not look the same front or rear when jacking up. Also when jacking up the front or rear you place more load and compress the other end a lot more. You cannot judge anything about ride height by how it looks jacked up.

 

Too many variables to account for during unsprung measurements. From the most basic starting point, for example, using a garage jack in the center front cross member....is the floor to fender height exactly the same for each side? An academic exercise to be sure, but curious.

 

Yes. The floor to fender height is the same when lifting up the RX. In other words, the car is leveled. However, the wheel height from the ground is different.