I ran into a strange issue the other day while doing the brakes. The new rotor is the right part #, but won't sit flush on the wheel hub. It almost seems like the inside diameter is just a sliver too small to seat all the way down. It was a problem on both sides (front wheels). Left the old rotors on for now till I figure it out. There's no significant rust buildup on the wheel hub that I can see.
Has anyone else run into this problem? Am I missing something or is it possible I just got a wrong part/bad quality part?
Rotor won't sit flush
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DieselSpider
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Re: Rotor won't sit flush
Just a film of rust can be too much as it does not take much. Mine had newer rotors in the front and bad ones in the back when I first got it so I swapped the front to the back and put new rotors up front. The new ones were tight going on a would not slide on flush until I wire brushed off the film of rust.
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So Cal Mark
Re: Rotor won't sit flush
we've seen some brands of rotors that have a small lip inside that contacts the hub, preventing the rotor from sitting flush. You can use a grinder to remove the lip or cut it on a lathe
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MikeHynes
- Posts: 51
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- Location: Central Il.
Re: Rotor won't sit flush
It sounds like a manufacturing problem. I've experienced the same thing. ID of rotor was machined improperly.
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micbrody
- Patron 2018
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Re: Rotor won't sit flush
I had same exact problem a week ago! I did post and there were many helpful answers. With that said, at end of thread I summarized the problem and solution. Here is a copy and paste of my explanation:
"Thanks for advice. You were correct. However, what I intuitively thought needed the most cleaning on hub was actually not the part that was causing problems:
The following is mainly for future members who have this problem:
I cleaned center of hub that has grease seal, that sticks through mounting hole of rotor, with wire brush and PB blaster. It still was wobbly and tight. I then just tested the rotor backwards to see if it would lay flush; and it did. This indicated that the problem was actually the outer rim of hub that "squeezes" into inside of rotor. The inside of rotor (not a brake surface; but where the hub goes into), if one looks carefully actually has a tiny 'ledge' that makes functional inner diameter smaller (really tiny).
In order to have this ledge pass the edge of hub, I really had to clean the outside edge of hub very hard; and took a hand file to remove any oxidation the brush would not remove. When I then mounted the rotor, I first applied the rotor pin screws hand tight; then it required light rubber mallet taps to seat the rotor. I finished tightening the rotor pin screws to spec. But at the end, it sat totally flush."
"Thanks for advice. You were correct. However, what I intuitively thought needed the most cleaning on hub was actually not the part that was causing problems:
The following is mainly for future members who have this problem:
I cleaned center of hub that has grease seal, that sticks through mounting hole of rotor, with wire brush and PB blaster. It still was wobbly and tight. I then just tested the rotor backwards to see if it would lay flush; and it did. This indicated that the problem was actually the outer rim of hub that "squeezes" into inside of rotor. The inside of rotor (not a brake surface; but where the hub goes into), if one looks carefully actually has a tiny 'ledge' that makes functional inner diameter smaller (really tiny).
In order to have this ledge pass the edge of hub, I really had to clean the outside edge of hub very hard; and took a hand file to remove any oxidation the brush would not remove. When I then mounted the rotor, I first applied the rotor pin screws hand tight; then it required light rubber mallet taps to seat the rotor. I finished tightening the rotor pin screws to spec. But at the end, it sat totally flush."