i had my springs on my car for bout 4 months now, but recently noticed that the rear passenger side is about 1cm higher than the other side, i know i installed something incorrect, but i cant figure out what? what can be making it 1cm higher? the spring is sitting right too and so is the top strut hat.

 

FYI ~ This is NOT that unusual for an Impreza to be a tad lower on the driver side. Why? Beats me... I have pulled a tape measure at my dealer to used Impreza's. Guess what at least 3 out of 5 are lower on the driver side. Why? Hmmmm...

Maybe 90% of the cars out there spend 90% of thier time with just a driver in the car??? Dunno.

At any rate if it bugs you that much, you can use a spring seat on the low side that is the correct thickness. Or washer the high side which will compress the spring a tad more and even it out... but really, why bother?

If you go the washer route you'll want a stack of flat washers the thickness you want to match that is 14mm I.D. and 25mm O.D. These will sit on the rod top below the threads and sit on the 1st shoulder of the strut rod. All this is UNDER the top hat.

 

but another weird part is that when i lower my car down/off from a lift, that rear passenger side shock doesnt quite compresses, and once fully on the ground, it is still almost fully extended, i have to go the back and press down and hold on the rear trunk inorder for the shock to compress back down, the shocks are in new condition still, never driven over pot holes etc...