GEN1 Q3 Safety: Inspect your lower control arms and subframe of the rear suspension!!

[S4'ed]

My 2015 Q3 suddenly started driving odd, crab-walking......the rear lower control arm rusted completely through, two large holes, and bent, causing a severe misalignment of the rear wheel.

The car has 103,000 miles, and has lived in the Northeast salt-belt since new. And I did rinse the undercarriage and wheel wells everytime the car was washed.

Sad that Aud spends so much effort with corrosion protection in the rest of the car, but cheaps-out in the rear suspension, with poorly painted steel parts.

Also, the rear subframe had lots of surface rust on it, I brushed some Loctite Extend Rust Neutralizer product on it.

I replaced both left and right arms yesterday.

I did not re-install the plastic/rubber stone guards. I actually think they are more for improving underbody aerodynamics.
I think these parts just trap more salt/dirt/moisture on the control arm.

These same lower rear control arms are used on many VW models (Golf, Jetta, Passat, CC, Tiguan, EOS), and I don't think any of those VW models have these plastic guards.
Q3 Control Arm2.jpg

[DeathBlow]

This is funny I had the same problem 2015 Audi Q3 and had to replace both arms. I also agree that the plastics trap salt that caused the damage but I did end up putting them back on but i added some coats of rust coating to them Also check your front brake dust shields i am working on replacing those also the whole bottom of them have rusted.