Back wheel coming off

[jambo101]

Friend of mine just called from several hundred miles away to tell me that the guy behind her informed her she was about to lose her rear wheel., i've heard of people losing a front wheel due to suspension failure but never a rear wheel, what could fail that would cause a rear wheel to come off. car is a 2010 Nissan Sentra.

Thanks

[TrapperL]

Loose lug nuts, broken wheel bearing, broken axle retainer, a Nissan car.

[sunsprit]

a not uncommon failure on cars like this is the wheel studs fracturing due to less than competent help in tire stores installing the lug nuts to a far higher than manufacturer's torque spec. The overtorqued studs won't always fail, but when one of them does while you're driving, the others may fail, too. The result is a "loose" wheel which may fall off while driving.

I had this happen repeatedly with Subaru cars and two local tire shops. They'd run down the lug nuts to over 100 ft-bls with their air wrenches. Subie spec on the high side is only 70 ft-lbs. A few times of overtorquing and the studs fail. BTDT when a rear wheel worked loose not too many miles away from the tire store. If it had happened once, I'd call it a fluke. But the same tire store has now replaced 4 !!! sets of studs on my cars due to the same failure. Even after I brought the causation to the attention of the tire store owner & managers, they still allowed their "techs" to install the wheels with the impact guns rather than torquing the studs to spec each and every time the wheels were off the cars. You'd think they'd have caught on after having to replace a set of studs on a car the 2nd time within a few miles of them repairing a slow leak on a tire. Perhaps my expectations of basic shop performance are too high.

A friend of mine in the tow business mentioned that he had contracts with a couple of local franchise tire stores ... where they had several cars per month towed in with this type of failure. Typically, people notice that their car is "wobbly" going down the road or that a wheel lug nut or two is missing from the wheel.

Of course, this is not the only mechanical problem that can cause a loose wheel in normal service. There are other components to the wheel/hub assembly that can fail for numerous reasons ... hitting a curb and overstressing the components, hitting potholes at speed, and so forth.

[jambo101]

I wish the woman would have the car towed to a local garage for at least a diagnosis but she is insisting it be towed from Lake George back to Montreal.

[jambo101]

Update/
She got the car to the mechanic here in Montreal,turns out it was loose and broken lug nuts. I'm sure any garage in Lake George would have tightened and replaced the lugnuts thus saving her many hours sitting in a tow truck.