Bad Rear Brake Drums from Napa

I had bad disc and drums from NAPA, O'Reilly's and Autozone. I now ask them to turn them before I bring them home. Several had high spots that would have caused excessive vibration and wear even brand new. Have the drums turned should solve your problem.

Sarge

It makes a big difference where and how to store these drums/disk on the shelf, they can warp in the box beleive it or not

Please explain.

Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my adddress with the letter 'x')

I'm talking experience Bill, Our parts department used to stack rotors and drums on top of each other, several together. We would install them and find the pulsation was really bad, we were charging the parts department the labor to machine them.. then they finally got smart and stored them differently and the warped rotors and drums stopped. not sure if the shelves they had them on were flimsy and caused this, you would have to ask someone who specializes in metal that question.

Drums are to be stored flat, not on edge. Rotors to be stored on edge, not flat. Used to be the boxes were labelled.

That said, chinese metalurgy leaves just a wee bit to be desired - and it is not out of the ordinary to have drums that are round when cold, and eccentric when warmed up. The Canadian made drums and rotors are quite often much better quality, but it is not unheard of to have bad ones from ANY manufacturer. They are finish ground while still "green". In years past, they were "aged" before final machining/grinding.

All it takes is for one person to drop the drum once after it's made and it's instantly out of round. It's always a good idea to turn any new drums when you get them.

Sometimes the same thing can be said for rotors.