I have towed a 2006 HHR for the last 3 years over 22k miles with automatic transmission at all speeds. The odometer now has over 36k also with no problems. It tows perfectly and like LeeB I would never know it's even there without the backup camera. I have all Blue Ox also and did not do any trimming for the base plate and it fits perfectly. When unhooked most people don't even notice the base plate. On the passengers side of the console is the fuse holder. The number 8 fuse needs to be pulled to disable the pass key system and stop battery drain. On the plus side when the fuse is pulled the ignition key can not be pulled out either. To keep from having to pull the cover of the fuse panel off and on, I went to the auto parts store and just purchased a rocker switch and in-line fuse holder with wire. Just pull the #8 fuse (third down from top right of fuse block) and attach the in-line fuse holder wires in it's place. Just use some blade type crimp on terminals. Place the fuse you removed into the in-line holder. Then attach it to the rocker switch. I mounted the rocker switch to the side of the heater duct right in front of the console. It's within easy reach from behind the wheel. Now to tow just put the key in Acc position, place the trans in neutral and flip the rocker switch and it's ready to go. I love the HHR and would buy another. It has lots of cargo room with fold down seats and gets 30 mpg. Maybe one or two less since ethanol but that's another story!
Wayne H. & Nixie Miller
2006 Newmar Dutch Star 4027