I can't believe this. The last couple of times I took the wheels off my girlfriend's Mini and it comes time to put them back on, I find that one or more of the lug bolts would shear when I torqued it ! Never had it happen on any of the cars I owned. Do Minis go through lug bolts ?

BVNitta

 

what torque value are you using, should be 120 +/_ 10 NaM (89 +/_ 7 foot lbs) I use 92 ft. lbs.




and what brand lug bolts?

 

Around 90 ft lbs and the bolts are stock. So I take it this is not a common problem with Minis ??

 

can't speak for the mark as a whole, but I've been rotating the tires on my
car every 5 k for 102,000 miles without incident since 02

 

I had one lug bolt out of the 16 that sheared on me. Actually it stretched, never being able to reach the needed torque. At 75 or so lb-ft it keps on tunring. Removing the bolt I find it to be quite elongated and hourglass-shaped. Since I put in locks, I used a bolt I had left over. Still, to have a bolt behave like this is not confidence inspiring. :impatient

 

i was surprised that my factory bolt did not break when i was
trying to remove it with my breaker bar. I had to almost bounce
on it.

dealer torqued it up so high it would not come off easily... from
just feeling, somewhere in the 135lbs/ft+ range.

they still torque up fine though... i use 90lbs/ft. im not sure how
many more cycles there's left on them though...

 

Suspect more the "+" part of the "135lbs/ft+ range" from your description.

 

I switched over to studs and lug nuts. My lug nut key has a flag on it: "No impact wrench! HAND TOOLS ONLY!"

 

speaking of over tightening, at the shop we are supposed to use torque sticks to limit the torque applied to the lug bolts with impact wreches. they work great. IF you use them. i see some guys who never use them and have their guns set on 4, which is max power. these guns deliver over 600lbs/ft of torque. no lie. that's what happened to you probably. some idiot overtightened them with an impact wrench.

so yeah, way over 135lbs/ft... if you had to stand on them with a 2ft breaker bar and you weigh... at least 150lbs, and you had to jump on. i'm guessing over 300lbs/ft at least...

 

Better to have them shear while you're torquing them and get them replaced than to have them shear while you're driving. I had that experience with my wife's car (a Buick..front wheel fell off while driving....all 5 bolts broke at the same place). Seems it's not very common, but it does happen. It is possible there was a bad batch of bolts. If the dealer broke it, they normally would just replace the bolt and not tell you about it.

We've since replaced all the bolts on the Buick. I would recommend you replace all the bolts on your MINI. Glad to know nobody got hurt.

 

#1 Be my guess too as I've had no issues with them...

 

I've an 02 with over 80k rotate regularly and no problems. Not intending to be a wise guy, but maybe you should check your torque wrench....they can get busted... Couple a bad mechanism with the long lever arm and you could be way over crunching....

 

Not normally or it hasn't been reported here regularly. I have never had a problem with mine, the only people to ever touch them or my brakes have been the factory and me. I just don't trust anybody else. Always by hand and torque down in three stages. It's very possible someone over torqued them before you started working on her car. I switched to studs and lug nuts a couple of years ago maybe you should consider doing the same.

 

Guys. Thanks for all your replies ! Yes, I torque in stages, always working on opposing bolts, finger tight first, wrench tight, torquing up to target, etc. I'm inclined to think then, that it could be car history.. Thanks again.

BVN

 

yah, you guys are probably right..

good thing they only removed one wheel...