Have run into a bit of a problem I've never encountered before. I took the car on a bit of a road trip two weekends ago (1993 RX-7), a total of about 700 miles round trip, no problems at all. Well today I'm doing some other things in the garage and notice that my passenger rear tire is very low on air, check the pressure, 5psi...and sure enough I find a screw in the tread. Ok no big deal I think, I jack the car up and just plan on taking off the wheel and taking the tire to get repaired.

Here is where it gets interesting, I go to loosen the first lug and notice that its slightly loose (I always tighten and loosen by hand, not with an air tool). What's stranger is that it feels almost like its skipping over the threads, but the amount of resistance I feel doesn't match what I have felt before with even smaller bolts. I move around to the other four, all with the exact same problem..and on top of that they will not tighten either. I can just turn the wrench for infinity and nothing happens, the wheel isn't off of the brake disc any distance at all, and the nut is still against the surface of the wheel. I even try the air wrench, nothing. WTF is going on I am thinking, I check a few lugs on the other tires, same thing. I notice there is a little but of rust around the inside of a couple, but not bad really.. it hasn't been that long since they were removed last, and I never over tighten..hand tighten to 70-75 ft. lbs always, nobody works on the car except myself.

I'm thinking, did someone mess with my car when it was parked on the street, or in the parking garage at work.. I doubt it. Did the long drive + tight suspension loosen and strip the studs in the hubs!?

Stuck with a flat I can't get off.
Matt

 

The studs are probably spinning in the hubs. The usual cause of this is lugs left insufficiently tight. 70-75 isn't spec (IIRC it's in the 80-90 range, don't have the figures with me) but it shouldn't have caused a problem, unless the torque wrench is faulty , OR if the lug nuts were galling against the studs before they clamped the rim to the hub.




Sadly, if *all* of them are spinning free, the hubs are probably all junk. Won't know until you manage to get it apart. Getting it apart is the *fun* part, sometimes you can pry the wheel away from the hub while hitting it with an impact, other times you have no choice but to get choppy. (Drill the stud out, not hack the wheel!)

 

I just looked in the manual, says 66-86 ft. lbs of torque. I'm pretty convinced somebody F'd with my car for every single one of these damn lugs to be behaving exactly the same on every wheel. I don't track the car, most abuse it gets is street driving, there is no way this happened naturally. I am NOT looking forward to drilling out everyone one of these things, especially with Volks on the car now, luckily the nuts themselves are open ended. Does anybody have a suggestion to get these off!!?

I did a bit of reading, what makes this such a pain in the *** is there is absolutely no way to access the studs from behind the hub.

 

Alright, not that I have had a bit of time to calm down and really think about it I've realized when this happened. I haven't had any reason to remove the wheels for about a year, in five years it's only been in someone else's shop twice, the last time was last spring when I had it repainted. One of the guys there must have used an air tool and overtightened every last one of the lug nuts. I'll call the owner tomorrow, its been so long I doubt he'll do anything for me but I at least want him to know he has a moron in his shop somewhere.

 

Overtightening will not cause the studs to get loose in the hubs.

 

That is an assumption until tested in reality. If the shear strength of the lug splines is less than that to strip the nuts or break the lugs, then it could posibly happen.

How else could it have happened? The shop took off the wheels and removed the lugs than drilled the holes out, then put them all back on?

The tire rack messed of a lug on my Protege last fall when they put on new tires.
The jerk must of tighten it when he though he was loosensing it, thus the treads are a little gauld. Before that it was perfect because I had put on new pads and all was well.

 

Not so. The splines only hold the stud in place until the stud is loaded, after that the tension against the head keeps it from turning, just like the tension on the nut keeps *it* from turning.

If the lugnuts were all loose enough for the wheel to walk around slightly under cornering/accelerating/braking loads, then the studs would be loaded in shear instead of purely in tension. The shear loads could easily wallow out the holes in the hubs.

It's extremely difficult to damage threads from overtightening. The wheel will sustain damage before the stud will. More likely, there was debris in the threads the final time the nut was torqued, and this caused the galling when trying to remove the nut.

 

I theory I understand your point peejay, I just can't fathom how I have the same problem on twenty lugnuts and studs.