Bobatbear

I left New York pulling the HHR behind our motorhome and noticed a front end hum when I used the car in SC, about a 1000 miles later. I replaced both wheel bearing hubs and the sound went away. After another 1000 miles the hum returned. Does anyone have anyone have similar experience after towing their car? If so, do you have any suggestions?

Lucky

Welcome to the site

I have towed my 07 behind the motorhome for over 6000 miles now with no problems at all.

I have had new wheel bearings fail fairly quickly on other a GM cars. It was when I was buying inexpensive ones online.

I replace wheel bearings from Napa now and had 0 new failures.

donbrew

CV axles? Rear hubs? Tires?
Hubs usually do more than "hum".

Oldblue

unless they don't know the words!!! But seriously it could be the rear hubs or the CV axle joints as Don mentioned

Lethal Tendencies

I replaced my struts/springs and sway bar links. 2 weeks later I replaced the sway bar bushings. After replacing the bushings I have developed a front end humming noise as described by the OP. It's a '08 with 126k miles on it could it be the wheel bearings? Bearing have never been replaced. Thanks

donbrew

Yes.

Lethal Tendencies

Thanks