Wobble braking

Discussion in 'Dodge Challenger General Maintenance' started by MajorChally, Oct 1, 2018.

  1. MajorChally

    MajorChally Member

    Posts:
    8
    Likes Received:
    0
    Joined:
    Apr 3, 2012
    Location:
    Seattle
    Hi all,

    For the last few months, I have been experiencing steering wheel wobble while breaking. Noticeably more so when breaking hard, seems less when just a short stop when coming to a light. I have heard that the factory rotors tend to warp easily. I have 67k on my 2012 SXT so I might expect the warping.

    Is it easier/less costly to have them pulled and resurfaced or just purchase new rotors and pads? If the latter is preferred, does anyone have ideas on brand/manufacturer? I do a lot of drag racing in the spring, summer months. I am thinking of going with the vented type, no drill or slot.

    Appreciate the knowledge input!
     
  2. IntimidatorRT

    IntimidatorRT Moderator Staff Member

    Age:
    63
    Posts:
    641
    Likes Received:
    126
    Joined:
    Aug 8, 2017
    Location:
    Rosepine,LA.
    i have the drilled and slotted rotors on mine front and rear. love them, no problems at all, dont see why you can run them on your sxt. but with that many miles you have , they may be warped and also check your pads to see how worn they are.
     
  3. F4Phantom2

    F4Phantom2 Member

    Posts:
    18
    Likes Received:
    6
    Joined:
    Jan 19, 2015
    Rotors and pads are so easily changed on these cars. Nothing at all like the old days when the job required mucking with tapered roller front wheel bearings. Now it's just remove the wheel, unbolt the caliper, HANG IT UP WITH A COAT HANGAR OR WIRE SO IT WON'T PUT WEIGHT ON THE BRAKE LINE, slide the rotor off. After pads are removed, use a piece of wood across each piston and a clamp to push the pistons back into their bores. Hopefully, you never added brake fluid so doing this will not cause the master cylinder to overflow. Personally, I never allow anyone to take the cover off my master cylinder.
     
  4. Diehard

    Diehard Full Access Member

    Age:
    77
    Posts:
    80
    Likes Received:
    15
    Joined:
    Feb 1, 2018
    Location:
    North Reading, MA
    It's not uncommon for rotors to form what is referred to as Hot Spots.These spots tend to cause the rotor to warp when heated due to hard braking. They are not necessarily warped when not heated due to braking. So it's hard to determine which rotor is the culprit.
    Not knowing how much they charge for turning the rotors these days, and considering the fact that turning removes material, which degrades the rotors further, together with the fact that the price of new rotors is not that bad, I typically just buy new ones and replace the pads while I'm at it.
     
  5. Vyper

    Vyper Active Member

    Posts:
    33
    Likes Received:
    17
    Joined:
    Nov 12, 2018
    Location:
    Middle Village, NY
    Brake rotors are cast in heat that is 3 to 5 times hotter than the most aggressive braking situation. They are designed to get hot (in excess of 1400 degrees) and high temperature from braking does not cause the rotors to warp.

    If the rotors are the culprit of your wobbly steering wheel, more than likely you have a lateral runout issue. Runout is a measurement of the difference between the high and low spots in the hub and on the rotor. When runout is out of specification, the uneven application against the pad will lead to disc thickness variation.

    Disc thickness variation is what makes people think their rotors are warped, but they're not. The rotors are just thicker in some spots because of the extra layers of brake pad material that was deposited to the high spots on the rotor, which probably all started because of lateral runout.

    I'm sure by now you've already decided which way to go between new or machined rotors, but I would suggest you address what caused the runout to move out of specification in the first place. It could be a number of different things but some causes include: runout from the hub mounting face, runout form the wheel bearing, a buildup of rust and corrosion between the rotor, hub and wheel. Uneven torque on the lug nuts can cause also cause runout.
     
  6. MajorChally

    MajorChally Member

    Posts:
    8
    Likes Received:
    0
    Joined:
    Apr 3, 2012
    Location:
    Seattle
    Thanks all for the replies!
    Vyper, I'll definitely take a close look at which it could be. I'll be pulling a wheel off tomorrow to get the power steering pump (leaking).
    If need be, I'll replace the rotors and pads instead of resurfacing.