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Torque Lug Nuts to Avoid Brake Disk Warp ?

solaraman2003solaraman2003 Posts: 88
edited March 6 in Toyota
Does anyone out there TORQUE their lug nuts when they mount their wheels on the Solara ?

My super-ace mechanic brother-in-law says that you SHOULD do this (to manufacturer's specs) so that you don't warp the rotors
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Comments

  • Mr_ShiftrightMr_Shiftright CaliforniaPosts: 44,850
    I doubt you could warp them with a hand wrench. This type of caution is meant for gorillas with air wrenches who smoke funny cigarettes during lunch.

    MODERATOR

  • bretfrazbretfraz Posts: 2,021
    I do this to avoid possibly damaging my rotors and my alloy wheels.
  • andre1969andre1969 Posts: 21,970
    I don't have a torque wrench though; I just tighten them to the point that they "feel" right. I think all rotors nowadays are pretty flimsy compared to the old days, and are just much easier to warp. On the plus side though, I think they're also cheaper and easier to just toss and get new ones, than the older styles.

    How much does a torque wrench run, anyway?
  • 0patience0patience Posts: 1,542
    andre1969,
    How much does a torque wrench run, anyway?

    Do you mean how much torque? Mine have 450 ft. lbs and 650 ft lbs. Enough to break all the lug nuts with ease.

    Or do you mean how much do they cost?
    You can buy cheap junk for about $50 or you can buy a quality Ingersoll Rand air wrench for about $129
  • bottgersbottgers Posts: 2,027
    It's more likely you'll experience rotor warpage due to brake heat rather than overtorqued lug nuts.
  • swschradswschrad Posts: 2,171
    if you overtorque a couple studs, and don't adequately torque another on the other side, considering how marginal rotors are getting I would not guarantee this won't happen.

    another way to get this result is to jam down lug nuts one by one. this gets to the funny result of the little centering conical section of the lug nut not going inside the wheel hole, but binding up on the outside of the hole on the rim's edge. first time you slip on pavement, you have a loose stud as the wheel reseats. good way to have lug nuts come loose and wheels fly off into the bushes, and a good way to break lugs. that kind of pressure is bound to warp hot, thin rotors.

    in any event, it's something you have to watch for when tightening down a wheel. and why it's supposed to be done in a star pattern in two or three passes.
  • Also, I'd like to point out that the owner's manual of my Toyota Solara DOES specify that you torque them. I haven't actually done this yet, since my car is brand new and I've yet to rotate the tires the first time.

    I just wonder how many people are aware of this and/or ensure that this is done when going in for service (i.e. tire rotation).
  • rubicon52rubicon52 Posts: 191
    There are at least a couple of reasons for tightening the lug nuts yourself with a torque wrench. One is avoiding warping the brake rotors. Another is avoiding cross threaded lug nuts.

    Even if you're using an air wrench, you should turn the lug nut on a few turns by hand and then use the air wrench. However, a lot of the gorillas as these discount tire places do all the turning with the air wrench. If the lug nut is cross threaded, the air wrench will still drive it on fine. The problem comes when you try to remove that lug nut and discover that its cross threaded.

    This happened to me once. I immediately went out and bought a floor jack and now do my own tire rotations.
  • Mr_ShiftrightMr_Shiftright CaliforniaPosts: 44,850
    I think this is quite over the top for the regular car owner. If you use the star-pattern for tightening, and use only reasonable force, I can't imagine how on earth you could warp a rotor unless they are making them out of frozen pizza dough.

    Also, a good torque wrench isn't cheap, and a cheap one isn't good.

    So just tighten your wheels firmly by hand and don't over-caffeinate prior to installation.

    MODERATOR

  • oldharryoldharry Posts: 413
    Right now, I have several torque wrenches, I torque every lug on every car, and working in an alignment shop, that is lots of lugs. About once a year, I send them off to Angle Repair for recalibration and repair.

    It is heat that warps rotors, but if they are not tightened evenly, they expand unevenly. Tightening by hand in several stages, you will most likely be close enough. Using a power wrench, even with "Torque Sticks" may end up with uneven tightness if one i tightened before the rest are snugged.

    A 50 to 250 pound foot Central Tools "click" type wrench wholesales for about $240. I buy mine through a wharehouse company.

    Harry
  • hank14hank14 Posts: 133
    Should any lubricant or grease be applied to lug nuts? I certainly don't want them flying off, but they can sure make a lot of noise when going on and off.
  • Mr_ShiftrightMr_Shiftright CaliforniaPosts: 44,850
    Lubrication may throw your torque readings off quite a bit, so be careful about that. I guess a little "never-seize" would be okay, but not a grease or anything like that as it will heat up and drool.

    Never seize is great stuff. Me myself and I prefer to install lugnuts dry.

    MODERATOR

  • hank14hank14 Posts: 133
    Thanks Shiftright. I'll go with that.
  • Warped rotors are common in todays vehicles. I've seen it occur after a panic stop. Also i've experienced warped rotors in my repair shop when lug nuts are installed incorrectly in sequence and over tightened with an air gun. I do not perform state inspections. When I brought my car in for an inspection, I asked the shop to torque the wheel they removed to proper spec with a torque wrench. They gave me an argument and said. "This was unheard of" I insisted and they complied with my wishes. The car manufacturers are reducing the weight of vehicles including rotors. In ending, if your rotor is slightly warped and you decide to replace the brake pads without cutting the rotors. a great deal of pronouced brake pulsation will result. If you don't agree that torqueing lugnuts is important, ask Mr. Goodwrench see what he says.
  • oldharryoldharry Posts: 413
    If you live in a state that uses road salt, a wire brush on your electric drill will clean off the rust when you have the wheels off, and you should not have problems. The wheel manufacturers also recommend cleaning the rust from the surfaces of the wheel and hub that meet. A build up of corosion may prevent the wheels from properly seating, resulting in vibrations and/or wheels that loosen in service.

    Harry
  • div2div2 Posts: 2,580
    Cars fitted with hub-centric wheels also need special care. The mating surfaces of the wheel and hub should be free of all dirt and corrosion. A thin coating of anti-sieze should also be applied to the mating surfaces. Failing to follow the above suggestions will likely result in a wheel that is well and truly stuck onto the hub-and that's the LAST thing you want when you are trying to change a flat on a dark rainy night. And yes, I hand torque the lug nuts/bolts on all my vehicles.
  • If you use that (the little 'L' shapped wrench) and tighten the lug nuts in a star pattern, you will not wrap the rotors, unless you are the Hulk. If you think about it, the thing is probably 1/2 foot long, so even if you weigh 200 pounds and you lean most of your body weight on the wrench, you'll apply less than 100 ft/pound. Most lug nuts are around 80 to 120 ft/lb (I'm not talking about an 18-wheeler, but you common passanger car), so it should be fine. I even undo and redo my lug nuts that way if I see/hear them using an air gun during service.

    Plus, if you have a flat in the middle of nowhere, and the previous time you had work done in your wheels the guy pounded the lug nuts with thee air wrench, you won't be able to get them off.

    Do them with the provided wrench, and you should be fine...

    My $0.02. G.
  • swschradswschrad Posts: 2,171
    at the side of the road in never-never-land in the rain at midnight, you will appreciate having had the foresight to put a two foot chunk of iron gas pipe in the trunk to use as a "cheater", or handle extender, to get those nuts off. hand-tighten with determination on mounting the spare, don't use the "cheater" again here.

    warning, danger, beware of possibility of personal injury when overstressing tools, never be put in a position where the tool could trap you against a firm object or could snap back and hit you, etc. and so on, voids lifetime tool warranties, support your local lawyer, and so it goes.
  • cutehumorcutehumor Posts: 137
    so let me get this straight, there's no way a person torquing their lug nuts can warp their rotors. only air guns can? yes, I'm no hulk. lol I do tighten them as much as possible though. I have had the unfortunate experience of changing a flat where an air gun was used. my hand was hurting for awhile. :)
  • Mr_ShiftrightMr_Shiftright CaliforniaPosts: 44,850
    I really don't think you can bend rotors by hand, no. I've never seen anyone do this although I suppose with a long cheater bar it might be possible. Rotors aren't pizza crusts, they are pretty sturdy just sitting there.

    MODERATOR

  • 0patience0patience Posts: 1,542
    One thing that you may want to understand about the rotors.
    As they heat up and cool down, they expand and contract. If the lug nuts are not torqued the same, over time the expanding and contracting can cause the rotors to contract differently on portions of the rotor.
  • Mr_ShiftrightMr_Shiftright CaliforniaPosts: 44,850
    Well I was assuming that the one same owner/installer would quite naturally torque the nuts more or less the same with a lug wrench--by tightening them "as tight as you can". I bet with that dinky wrench the torque readings would be approximately close to one another.

    MODERATOR

  • swschradswschrad Posts: 2,171
    you are NOT going to be tightening the nuts down to a consistent pressure against the rotor. you will put a similar FORCE against all the studs, but you will have differing thread resistance on thread sets that are not clean, dry, and non-lubricated than on thread sets that are.

    and if you do them one at a time, I guarantee you will NOT have one or more of the lug nuts centered in the hole of the wheel... where the taper at the end of the nut will not have entered the wheel to make a final centering adjustment... and those will loosen in just a few hours of driving. possibly even spin off into the weeds.

    just two more ways to have uneven force against the rotor... and when it gets hot, it will expand wherever it can. if there are gaps between the wheel and the rotor... and there WILL BE sooner or later if all the nuts aren't snugged up the same... the rotor will be encouraged to distort.
  • 0patience0patience Posts: 1,542
    I'll agree that normally tightening them by hand is not going to create much problems.
    It is when impacts are used when the most problems are caused.
  • Mr_ShiftrightMr_Shiftright CaliforniaPosts: 44,850
    I think the owner's manual gives you proper directions for how to tighten the studs by hand anyway.

    In my opinion, if they install a rotor that can actually be bent by changing a spare tire with a lug wrench, then they are REALLY cutting the corners too thin in making the car. Reminds me of when GM expected Corvair owners to put just the right amount of air in front and rear tires (different pressures), accurate to within a pound or two, or face dire consequences--well, guess what?

    MODERATOR

  • just4fun2just4fun2 Posts: 461
    are saying, but, I can't imagine how a rotor can be warped by over tightened nuts. On my van the wheel studs are in the wheel hub. Now the rotor slips over the studs and the tire/rim goes on next. You are basically sandwiching the rotor between the hub and rim. Now with the thickness of the hub/rotor/rim, how can that much metal be twisted by over tightening the bolts?

    I would think that the tire/rim going around a corner in the road at 45 mph would put more pressure on the studs than over tightening the wheel nuts would. Where am I going wrong here?
  • swschradswschrad Posts: 2,171
    in fact, it might act as a collar to cushion the uneven force away from the stud pressfits in the wheel or hub. but as the rotor heats up and cools down while you drive and brake, it expands and contracts unevenly due to the big old gap where you have a loose bolt. guess what happens when you hit a puddle with a hot brake rotor when it's unevenly expanded? -- it gets stressed. apparently these parts aren't tempered enough to stress-crack, but they will warp at that point from the sudden quenching. the warp will be high on one brake pad, causing uneven heating from then on... and it pulls the warp.

    you don't have to warp 3/4-inch to make a shudderingly obvious difference, just a few thousandths of an inch (probably 10+ thousandths, but I don't gage rotors for flatness, but that seems a reasonable out-of-flatness to cause issues.)
  • 0patience0patience Posts: 1,542
    Some of the vehicles, the rotors are stamped metal and not cast.
    Stamped metal is extremely succepptable to warpage, which is why some aftermarket replacements for vehicles like the Lumina are cast, machined rotors.

    Understant that the hub of the rotor affects the braking surface. If you pull a bolt down, the face of the rotor flexes. As it heats and cools, it will set in a position.
    Most often, this only happens when air wrenches are used. It can be corrected by having the rotors turned on the vehicle, but then again, if they are stamped rotors, then replacing them is the best option.
  • bcarter3bcarter3 Posts: 145
    I've been in aviation maintenance for 43 years. Virtually all fasteners have a designated torque and some of them are considered mandatory. While a car or truck may not require the same degree of care, I use a service manual for my vehicle and always use a torque wrench if torque is mentioned. If anyone in my family has to change a tire on the road they can do it with the tools provided with their vehicle. We do not carry "cheater bars". My torque wrenches are never used by anyone other than myself and are kept in a protected case. A damaged torque wrench is no better than a breaker bar. Having said all that I will admit that a good mechanic can recognize when a nut or bolt is tight without stripping the threads.
  • Mr_ShiftrightMr_Shiftright CaliforniaPosts: 44,850
    I've worked on small aircraft and the standards are considerably higher for mechanics and what they are supposed to do and not do. Also, everything on a plane is light AND strong. It's the "AND" part that makes the parts expensive, not the "light" part. Some automakers get the light part right but not the strong part.

    My personal opinion is that rotor thickness plays a large part in rotor life. That thickness can be achieved a number of different ways (design-wise) but I have seen some pathetic rotors on certain new cars. They seem more interested in making them look nice than in giving them durability.

    MODERATOR

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