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  • Stupidity is expensive

    Had a good one today,lady came in to the shop last week with a front wheel drive hub and bearing assembly a new bearing and four new wheel studs wanting the bearing and studs changed.No problem,routine job,pressed it apart,pressed the old studs out,new ones back in and pushed the whole assembly back together.I noticed that all four studs were broken off,but that's not too unusual given how tight some tire shops gun the lugs down now.

    Monday she calls up,tells me the four new studs broke off,the wheel came off and put her car in the ditch.She had to have it towed and she said we owe her for the tow and the repairs because her mechanic told her the studs weren't pulled tight with the spindle flange(no way in hell).So we sent one of our guys over to the car,he pulled the assembly off the car and brought it and the tire and rim back to the shop.

    This a 20xx Honda Civic,but the rim says FORD in the center cap.Turns out she had warped a rim a month back and her "mechanic" got one from a salvage yard and put it on the car.Then a week later the first set of wheel studs broke,then all the fun started.

    So a quick check confirmed the Honda has a larger center pilot than the Ford Escort the rim came off by a good 2mm and her "mechanic" just ran the lugs up anyway because according to him "the pilot doesn't do anything anyway"-and what a jacka!! he is too.

    So I gave her a stack of hi-res photos of the studs,the documentation regarding the pilot diameters and a written report from a mechanical engineer including his PE stamp.Told here here-go sue the stupid [email protected][email protected]#~! before he kills somebody.
    I just need one more tool,just one!

  • #2
    While it might seem like the cause of failure was the non piloted wheel, it might not be. I say this because of a couple of things, one being my experience as owner/driver and later as crew member on a Street Stock class oval track race car where we used non piloted rims with stock wheel studs and 1" wheel nuts and we never had a single problem nor did I see anyone else have a single problem. Nothing side loads a wheel like oval track racing does! (We won 8 championships in a row with the car I crewed on too btw.) Another thing is I've also ran non piloted rims on a 1980 Chevy 4x4 3/4 ton truck for years without any issues ever albeit rarely hauling much weight. (No cracks about my girlfriends either, eh! )

    I think it's highly likely you nailed the cause of the failure when you said "I noticed that all four studs were broken off,but that's not too unusual given how tight some tire shops gun the lugs down now." I'd bet my own money that the wheel nuts were severely overtightened and just a bit more load on them from normal driving put them into failure mode.

    Either way, it was her mechanic's fault!
    Location: Saskatoon, Saskatchewan, Canada

    Comment


    • #3
      It may also depend on the lug nuts themselves, as if the wheel is hub-centered, then the lug nuts are generally flat, vs when it is lug-centered, and the lug nuts are tapered to position the wheel correctly.

      Odd are, the stock car would be using tapered lug nuts to go with the lug-centered wheels.

      Comment


      • #4
        The pilot was BIGGER than the hole in the rim. this prevented the wheel from contacting the hub and leaving a gap between wheel and hub. Result is all cyclical loads, cornering and simply rolling vehicle weight will be seen by the studs and cause fatigue failure. TWICE.

        Read up on bolted joint diagrams to understand:

        http://www.boltscience.com/pages/basics1.htm

        If the pilot was smaller than the hole in the rim it probably would have been fine.

        Comment


        • #5
          Originally posted by wierdscience View Post

          So a quick check confirmed the Honda has a larger center pilot than the Ford Escort the rim came off by a good 2mm and her "mechanic" just ran the lugs up anyway
          Thats just crazy!! And some mechs wonder why there is a bad rap in the mech business. JR
          My old yahoo group. Bridgeport Mill Group

          https://groups.yahoo.com/neo/groups/...port_mill/info

          Comment


          • #6
            Some peoples kids lol serious business... you gave her everything needed to hang his ass with - perhaps he will think twice when trying to pass the blame onto someone way more intelligent than he is... what a world...

            she was actually going to go easy on you with her demands - with him after being caught in a lie - probably not - so be it...

            Comment


            • #7
              Originally posted by strokersix View Post
              The pilot was BIGGER than the hole in the rim. this prevented the wheel from contacting the hub and leaving a gap between wheel and hub. Result is all cyclical loads, cornering and simply rolling vehicle weight will be seen by the studs and cause fatigue failure. TWICE.

              Read up on bolted joint diagrams to understand:

              http://www.boltscience.com/pages/basics1.htm

              If the pilot was smaller than the hole in the rim it probably would have been fine.
              Absolutely right.

              Lug centered is fine. A gap between wheel and hub - not so much.

              Comment


              • #8
                Another reason I do all of my own automotive work, I've seen worse examples of "mechanics" at dealerships that charge $120/hr.
                Not to besmirch all auto mechanics, there still some very good ones around. If you find one treat him well.

                Unfortunately there is still a very large segment of "professionals" around who still have not grasped the concepts and differences between hub piloted wheels and stud piloted wheels. The design and function of their respective wheel mounting hardware is also totally different in design and execution.
                But yeah bolting a hub piloted wheel onto a hub that has a pilot 2mm bigger than the one that the wheel has just screams stupidity.

                Guys like this "mechanic" kill people by inflicting the effects of their ignorance onto the the unsuspecting.
                Home, down in the valley behind the Red Angus
                Bad Decisions Make Good Stories​

                Location: British Columbia

                Comment


                • #9
                  Originally posted by wierdscience View Post
                  her mechanic told her the studs weren't pulled tight with the spindle flange(no way in hell).
                  I hate that phrase "my mechanic told me". If the person has a regular mechanic, then why did she come to you? Always means trouble.

                  Comment


                  • #10
                    Originally posted by Arcane View Post
                    While it might seem like the cause of failure was the non piloted wheel, it might not be. I say this because of a couple of things, one being my experience as owner/driver and later as crew member on a Street Stock class oval track race car where we used non piloted rims with stock wheel studs and 1" wheel nuts and we never had a single problem nor did I see anyone else have a single problem. Nothing side loads a wheel like oval track racing does! (We won 8 championships in a row with the car I crewed on too btw.) Another thing is I've also ran non piloted rims on a 1980 Chevy 4x4 3/4 ton truck for years without any issues ever albeit rarely hauling much weight. (No cracks about my girlfriends either, eh! )

                    I think it's highly likely you nailed the cause of the failure when you said "I noticed that all four studs were broken off,but that's not too unusual given how tight some tire shops gun the lugs down now." I'd bet my own money that the wheel nuts were severely overtightened and just a bit more load on them from normal driving put them into failure mode.

                    Either way, it was her mechanic's fault!
                    Think you missed the 'Larger pilot on the Civic then there was on the Ford rim' part. That means he either stretched the studs or bent the rim to make it fit. I've used rims with bigger pilots than the axle on my trucks with no trouble ever, but if I ran into a rim with a smaller pilot, I'd go looking for another, or grab 3/8" spacers I have in the shed would never just crank them down.

                    Comment


                    • #11
                      Originally posted by kendall View Post
                      Think you missed the 'Larger pilot on the Civic then there was on the Ford rim' part. That means he either stretched the studs or bent the rim to make it fit. I've used rims with bigger pilots than the axle on my trucks with no trouble ever, but if I ran into a rim with a smaller pilot, I'd go looking for another, or grab 3/8" spacers I have in the shed would never just crank them down.
                      Darn, beat by everyone!

                      Comment


                      • #12
                        Originally posted by JRouche View Post
                        Thats just crazy!! And some mechs wonder why there is a bad rap in the mech business. JR
                        Yup,just a few bad apples,worst is he robbed her first time around IMO.If I heard her right he charged her $350 to pull the assembly and re-install it.On a Civic that's about an hour each way IIRC.
                        I just need one more tool,just one!

                        Comment


                        • #13
                          Originally posted by MikeWI View Post
                          I hate that phrase "my mechanic told me". If the person has a regular mechanic, then why did she come to you? Always means trouble.
                          We do general machine work and fabrication and one of the services we offer is press work removing bearings,straightening things etc.Several shops around town send their wheel spindle work over either because they don't have a press or the puller set to remove them,plus we get a slew of DIYers.
                          It's a money maker for us and 99% of the time everybody is happy and all is well,of course there is always the 1%er's that make life interesting.
                          I just need one more tool,just one!

                          Comment


                          • #14
                            Yes and this one had a burr of Aluminum 3/4 the way around the rim bore and about 1/8" deep where the rim tried to stretch over the pilot.So I figure 1/8" off kilter at the pilot,that must have translated to 3/4"-1" run out at the tread.

                            If he had just put the car in neutral and rolled the wheel around a couple times he would have seen it.
                            I just need one more tool,just one!

                            Comment


                            • #15
                              I had a customer get bearings replaced on a tire tread grinding machine. The machine shop took the shaft back to their shop and used a 100 ton press to get the pulley off, then pressed it back on the same way. The machine still sounded bad with new bearings because the pulley wasn't in the right place. I showed the customer and told him I'd have it fixed in a few minutes. That was when he told me about the press. He about fell down when I loosened the three bolts on the TAPERLOCK bushing and moved the pulley over by hand! Remember half the class is always below average.

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