First of all, it's a quick crime. Call, call, call! It mostly happens at night, and it happens fast. Thieves park next to a parked vehicle -- usually a tall one that they can slip under easily -- and they blast loud music to drown out the sound of their power tools.
If you see someone lying next to a parked vehicle or acting as a lookout in a double-parked car, call 911 and report "suspicious activity." If you have a video system, see if you have the license plate number of the thieves' vehicle recorded.
CWB Chicago has an article on recent local thefts and the attempts to stop them.
To repeat a previous post from 2014:
"The thieves use a Sawzall, which enables them to get under your vehicle and remove the catalytic converter in only a few minutes. They get $50 or so for the precious metals contained in it, and it costs you considerably more to replace it.
In previous posts, we repeated the advice of experts: "There are deterrents --
- engraving your license plate number on your catalytic converter,
- having it welded to the car frame, or
- asking a muffler shop attach some extra metal to make it harder to remove.
- The best deterrent is to look out for your neighbors and call 911 if you see anyone inspecting their cars or lying or crouching near it."
We imagine that any mechanics shop or body shop in the area would be glad to weld some braces to your car to discourage theft. Cheap compared to the hassle and frustration of having to have your car or SUV repaired. Just another joy of living in a big city."