Lug-Centric VS Hub-centric

Discussion in 'SRT Hellcat Wheels and Tires' started by Tire God 2.0, Apr 30, 2016.

?

Was this helpful?

  1. Yes

    100.0%
  2. No

    0 vote(s)
    0.0%
  3. I still don't get it

    0 vote(s)
    0.0%
  1. Tire God 2.0

    Tire God 2.0 Senior Hellcat Member

    Joined:
    Apr 24, 2016
    Messages:
    317
    Likes Received:
    75
    Trophy Points:
    58
    Vehicle:
    Challenger SRT Hellcat
    Hopefully this will help answer any questions about the way a wheel fits on your car or truck. Lug-centric means the wheel is centered by the studs rather than the hub, and hub-centric means the wheel is centered by the hub rather than the studs. The proper and safest fitment is hub centric, and here is why.
    A long time ago, there were OEM lug centric wheels (like the 1940's and such), but because of this, they made the drivers side studs and lugs reverse threaded. Why you ask? Because they understood the physics behind having a lug centric wheel. When a wheel is centered on the studs, the studs are then the only point that carries the load of the vehicle. And when this is the case, the lug seat(cone seat) is the only thing "centering" the wheels. But under harsh conditions(heavy braking) it can cause the lug nuts on the drivers side to actually loosen. When you slam on the brake, the weight of the car goes all towards the front, while the wheel and tire are applying equal and opposite force the other direction(this is the physics part). And when the wheel and tire are applying forces the opposite direction(towards the rear) it puts equal and opposite forces on the lug nuts. Meaning with enough forces the lug nuts will loosen and that's not good. So the fix for this back in the day, was to have reverse threaded studs and lugs on the drivers side. But, while this fixed the issue of them coming loose, what it did was the opposite and tighten the lugs, sometimes to the point where the lug torque ended up being 50-100 ft lbs more than it was supposed to be and it stretches the studs pass their yeld point and the studs become brittle, and you hit a nice bump and the studs snap in half and take the lugs with them. This is why we don't have reverse threaded studs anymore on passenger vehicles, and why all OEM wheels are hub centric from factory. Also, the weight of the vehicle on the studs can bend or break them, and cause other issues like prematurely worn wheel bearings, broken CV axles ect. The studs and lugs are there to provide proper clamping force to keep the wheel mated the the hub under lateral loads. The hub pilot is there to take the stress of radial sheer forces (up and down).
    I'm not saying "Don't do it!!!" You might never have this issue. But considering the really heavy, big hairy American winning machines you have, I would at least consider it. Most high end wheel manufacturers will custom build them for your hub size, and the ones that don't will offer hubrings to make the wheel center on the hub like it was intended to be. I even hear that there is reduced amounts of wheel fatigue with hub-centric wheels, because the mounting pad where the hub bore is, is the thickest strongest part and can distribute the stress more evenly.
    Hopefully this was good information for you guys. If you have questions or concerns feel free to ask.
     
    • Useful Useful x 3
    • Like Like x 1
    • Agree Agree x 1

Share This Page