Brake drum balancing?

[GASnBRASS]

I received a pair of Centric premium drums and one was the typical black and blue box centric that's all cast with a welded balance weight, and one centric "posi-quiet" drum that has no balance weight but the entire outer diameter is machined. Both have the same 122.67021 part number but are clearly made different. The outer drum edge is also thicker on the machined posi-quiet drum, not sure if that would help resist warpage.

Is the posi-quiet machined to balance? Is there a preference to one method over the other?

 

[pagrey]

It's a drum, if it fits it is super good. Excellent in my opinion.

 

[Jerry Bransford]

I dunno but it's hard to differentiate brake drums and that's probably their attempt at doing that.

 

[Apparition]

Blaine would be the one to ask

 

[GASnBRASS]

@mrblaine have you seen mismatched drums like this with the same part number from Centric, or is this just a case of two different factories in China making the same part two different ways? I'm mostly concerned about the lack of balance weights on the machined drum unless it's turned til balanced.

 

[mrblaine]

@mrblaine have you seen mismatched drums like this with the same part number from Centric, or is this just a case of two different factories in China making the same part two different ways? I'm mostly concerned about the lack of balance weights on the machined drum unless it's turned til balanced.

Lack of weights doesn't mean they aren't balanced.

 

[PJTJ]

I received a pair of Centric premium drums and one was the typical black and blue box centric that's all cast with a welded balance weight, and one centric "posi-quiet" drum that has no balance weight but the entire outer diameter is machined. Both have the same 122.67021 part number but are clearly made different. The outer drum edge is also thicker on the machined posi-quiet drum, not sure if that would help resist warpage.

Is the posi-quiet machined to balance? Is there a preference to one method over the other?

View attachment 275001

View attachment 275003

View attachment 275043

View attachment 275072

Any update on these? Have the same issue where the two drums are visually different thickness on the edges (neither has a balancing weight) and not sure if it’s cause for a return or if they are good to install…

 

[P man]

Any update on these? Have the same issue where the two drums are visually different thickness on the edges (neither has a balancing weight) and not sure if it’s cause for a return or if they are good to install…

If they are the same part number and look identical minus the edges and weights I would install and forget

 

[PJTJ]

If they are the same part number and look identical minus the edges and weights I would install and forget

Thanks- pretty much identical (some difference in the finish); the difference in the width of the “ridges” doesn’t look to equate to any difference in the overall width of the outer wall or the interior diameter.

 

[mrblaine]

Thanks- pretty much identical (some difference in the finish); the difference in the width of the “ridges” doesn’t look to equate to any difference in the overall width of the outer wall or the interior diameter.

View attachment 353602

View attachment 353603

Centric was taken over by an investment group, then there is some affiliation with Raybestos, then there is a big pile of stinky bullshit. We've had to find alternate sources of premium quality rotors and drums. We still get what we can from Centric but they do not inspire the same confidence that they used to. Their price increases have all but ruined a very long term relationship. Fortunately a lot of the top personnel have split off and started their own brake companies so we are able to source quality parts from them at higher but more tolerable prices. Good luck, we got in a batch of loaded backing plates and they are not the same quality we used to get from them.

 

[Vtx531]

Is the posi-quiet machined to balance?

I don't think that's a thing. It would take off runout (doesn't matter on the outside) and maybe improve balance but not balance it (could even make balance worse). If you look at brake rotors, they machine a little bit on of the edge at one little spot for balancing, not all the way around.

 

[PJTJ]

Centric was taken over by an investment group, then there is some affiliation with Raybestos, then there is a big pile of stinky bullshit. We've had to find alternate sources of premium quality rotors and drums. We still get what we can from Centric but they do not inspire the same confidence that they used to. Their price increases have all but ruined a very long term relationship. Fortunately a lot of the top personnel have split off and started their own brake companies so we are able to source quality parts from them at higher but more tolerable prices. Good luck, we got in a batch of loaded backing plates and they are not the same quality we used to get from them.

Thank you Mr. Blaine! That’s a bummer to hear about Centric.