Hub centric rings not sitting snug
 

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I'm trying to put on some hub centric rings I got from conceptZ and for some reason this one wont fit snug like the other one did. Would it be bad to just put the whe back on like that? I was running without them previously.

Pull the ring back out and make sure there's no crap stuck on either ID or OD. Next, see what is interfering with the fit and use a soft hammer to tap around the ring and see if it will seat with a little persuasion. In my experience, those hub rings are either too tight (rarely) or loose (commonly).

I cleaned around where it sits and still nothing I used a rubber mallet to try and force it into place but still nothing. The opposite wheel worked first try, it's weird this one doesn't want to sit in place. I went ahead and just mounted it with it like it is and did not seem to notice any difference driving.\

edit: oddly enough both of my driver sides fit perfectly fine only the passenger side ones would not fit snug.

Check the size marked on the ring. You may have one that's 73.1 (very common size) and your wheel hub holes are 73.0. That 0.1mm does make it snug.

You're really not going to hurt anything without the ring in the short term. Long term, however, not having the proper wheel-to-hub sizing (as in hubcentric wheels) can lead to vibration and/or uneven tire wear. But again, not a drastic-and-fatal-if-you-don't-have-'em kinda thing.

Hub rings are cheap. I always have 2-3 spare sets in my tool box drawer (the one with the 6-7 sets of lug nuts of varying types, laff). I note you are using metal. Personally, I don't like the metal ones because they gall and get stuck to the hub pretty easily. And have found they don't last any more wheel/service changes than nylon. And the nylon ones are like $4-5 a set.

EDIT: Just went back and looked at your your 2nd picture again... not sure if it's the angle of the pic but that ring looks like it's protruding some 2-3mm from the mounting surface. That's NOT good. One of two things could be happening....

With metal rings, either you've compressed the ring into the wheel when it's bolted on and thereby making it nearly impossible to extract from the hub hole (not terrible because it essentially just becomes "part of the wheel") OR....

The wheel mounting face isn't flush to the hub and is hanging 2-3mm from it. This is NOT a good scenario as true torque on the lugs hasn't been achieved or the wheel is now "floating" above the hub and could lead to losing torque to the lugs and/or vibration/wobbling of the wheel. Take them off and check. If it is actually protruding from the wheel instead of being flush, take the ring off and get new ones that fit properly. Again, the hub ring should fit all the way into the hub hole of the wheel and sit flush with the mounting pad.

That was a picture of me pointing the wheel downwards, it ends up just falling out. My driver side front and rear ones fit perfectly just the passenger ones did not. I also do have steering wheel vibration at 80+ mph. The driver side ring helped reduce that vibration but it is still there and seems to be more pronounced than the normal vibration at those speeds. I also had my wheels double checked to make sure they where balanced out to 0.

I am using my old tires with my new wheels and on stock wheels I did not have any of these issues at all.

So my question stands: Is the hub ring sticking out from the wheel face because you can't get it in all the way or is it flush?

If it's not flush, that vibration at speed could be your wheels are loose and wobbling on the hub ring as I alluded to!

There is no such thing as "normal vibration". Properly aligned, good suspension, wheels/tires balanced and mounted properly = zero vibration.