Grinding noise after changing wheel hub assembly

So I changed both front wheel hub assemblies on our 2012 Sentra day before yesterday. They were cheapies but its just to get by till tax return time. After getting everything put back together there’s a grinding noise. I first thought it was the rotor dust shield but that wasn’t it. It’s the wifes car and she has to have it to drive to work and back so she insisted on taking it to the shop. They said it was something not being torqued to specs. Picked it up and its still doing it. It only makes the sound for about 3-4 blocks and it goes away and sounds normal. Now they say they “think” its the bearings and want $582 to change them. they said they took it down to just the hub and it still does it and that’s why they think its the bearings. Is there something I could have done or not done or did wrong just changing the hub assembly? I feel like if it were the brand new bearings they would do it constantly. Thanks for any input.

Also, the temperature outside here has been in the negatives so maybe it’s totally unrelated?

Did you tighten the axle nut to the proper torque?

Tester

@Tester Yes, 140 ft lbs is what the service manual said

I guess you get what you pay for.

Tester

@Tester That was sort of my thought but I took it out driving for about 30 minutes about an hour ago and it grinds like if the dust shield were rubbing against the rotor for about half a block then nothing, absolutely quiet the rest of the trip. Not even the usual bearing going bad hum.

Go back and check if any of the hub assembly mounting bolts have come loose.

Tester

Going to check that when the temp warms up. On a weird side note, it wasn’t doing it when they pulled it out of the warm garage at the repair shop and drove it around. But did when we went to pick it up.