So, I'm taking a right turn onto the freeway onramp yesterday and BOOM my E55 starts thumping and I come to an immediate stop. Turns out all 5 of my cone-style lug nuts sheared off on my driver's side rear wheel and it came off! Good thing I was riding low with the airmatic or the wheel might have shot out of the wheel well. In December 2013 I had some Forgestar F14s professionally installed (whatever that means) by a local shop in SoCal. No one has touched the wheels since then. Who here thinks the supplier/installation shop should pay for the damages? Has anyone else had this experience? What do you think the cause was? Faulty lug nuts or improper torqueing on installation maybe?

 

**** luck? Its def not the shops fault since its like 9months later... and DEF not the wheel manufacturer's fault, cause the wheel didnt fail. My guess is maybe a bad batch of lug nuts? But then again... Ive never seen a lug fail ever

 

Wonder if they were grossly over or under torqued... All five failing is pretty strange.

 

Had this happen to me on my front driver's side wheel, and the shop that repaired the wheel (it had bent) didn't put it on right. My fender got bent up and of course my wheel got torn up. They paid for the repair of the fender, and then replaced the wheel. Unless you don't drive your car too often, 9 months is a long time. Did you need to use a hub ring?

 

What is torque of bolts on the other 3 wheels?

 

I didn't see them do the installation, but I don't think they used a hub ring. Is that important?

Not sure what the torque of the bolts is on the other 3 wheels. I could have MB check that.

 

So your lug nuts fail (probably because they were defective and over torqued), but your title seems to indicate this had something to do with F14s ???

 

You're right, probably not the most accurate title. However the lugs and the F14 were procured and installed by the same shop. I'm not sure if the lugs came from Forgestar with the wheels or from somewhere else.

 

Hub ring is very important if the center bore of the wheel is not the same size as the hub on the vehicle. Did you have a little shake at all? Only reason I say its so important is because without them it puts all the stress on the bolts to hold the wheel straight up and to hold them into the hub as well.

 

^ absolutely!

It looks like your hub was damaged, but it is impossible to tell if that damage was caused before or after the damage. If the wheel was moving around because it didn't have a hub ring this is very likely. I'm not sure that I've ever seen a "professional install" without hub rings though. The shop would take on too much liability, and if they did it without, you *should* have been notified. I've never known anyone to not say "you may need some hub rings with that"...

 

How far in do the lug bolts go into the hub ? 1/4 inch 1/2 inch meaning are they too short possibly ,can you back out the rest of the broken bolt and see what's left of it

 

I'll have to look at the other 3 wheels to see if they put the hub rings on, but I don't think they did.

@mobhouse - no the car didn't shake, or at least I didn't notice it. I had the alignment done by MB right after putting the wheels on in December and it drove well.

@centerline - good point. I won't be able to back the bolts out myself, but the car's at MB now. I'll have them check the bolt length. Even if they can't back them out, I suppose they can check the bolts in the other rear wheel for size.

 

Someone else recently had issues with shearing lugs and I believe it was determined that he was running the wrong type of lug seat.

 

With new wheels the lug nuts should be re-torqued after about 500 miles. I know that many times it doesn't get done and everything works out, but if they start to work loose (which happens frequently) they will eventually sheer off just like this.

Hub rings allow wheels with larger bores to fit on a car with smaller hub diameter without shaking because they make sure the wheel is centered properly. However, lots of vehicles on the road with "studcentric" vs. "hubcentric" wheels and they don't fall off, it's just a lot harder to get them centered perfectly so shaking is a lot more common.

 

Who installed the wheels? I would see what type or brand of lugs they are using...That should NEVER happen.

 

The F14 have a center bore of 74.1. MB wheels have a center bore of 66.56 so you would have to use some rings to make sure the wheel is centered.
It is simple without the centering ring the lugs cannot take the load of the car not matter how strong they are

 

Ah-ah!, the EXACT same thing happened to me with my Lexus GS
http://www.clublexus.com/forums/gs-t...ml#post3311214.

Bottom line, hub-centric wheels and proper re-torquing are a must!

 

Wow... interesting.

I got news for you bro. The same thing happened to me, except, I caught the problem before that (your situation) happened.

Same wheels and all... on my way to work, I swung by America's tires in Carson to put some air in my tires. The technician called me over to my rear right wheel and said... "I'm sure you probably already know, but you're missing a lug bolt."

My initial reaction was... i'm missing a what?!? I just slapped on new tires about 2k miles ago. No one has touched the wheels since. Just to be safe, i asked the technician to re-tighten all bolts on all four corners. As soon as he placed his torque wrench on the very first bolt, it snapped off. As in... half of the bolt was still in the hole.

America's tires didn't have the exact lug bolts i needed, so i asked the tech to pull a bolt from the rear left and place it on the rear right. 4 bolts on each wheel.

i waited a few days until i had time to swing by my shop in Huntington Beach. My guy ordered me a fresh set of bolts all around.

Funny thing was... as he removed all lug bolts, they ALL had small tiny hairline cracks on them. As in... ALL the bolts were ready to give out. It was just a matter of time.

 

You mean the remaining 19 bolts had hairline cracks ?
While on this subject ,how far into the hub should the lug bolt go ?

 

While on the subject of lug bolts and proper torque, how many foot pounds should I tighten them to? I want to check my bolts because of this thread.

 

Holy smokes!! That is crazy. Thank god your ok

 

Correct. Some bolts had smaller/bigger hairline cracks than others. Easy to tell that they were in no condition to be torqued onto a car. Dangerous... but i'm glad I found the problem, before the problem found me.

I don't have the exact measurement of my lug bolt, so i don't want to give you an inaccurate answer. Perhaps someone can chime in.



95lbs - 110lbs

Everyone on the forum has different specs and reasons for their specs.

If i'm not mistaken, i believe the manufacturer's specs on the stock AMG wheels are somewhere around 90lbs.

 

Lug nuts/bolts should be tightened NO LESS that 3 FULL turns... I prefer nearing 4. ~85lb/tq on avg. - Invest in a Tq wrench. And yes, over tightening can cause these scenarios. I hate impact guns from shops unless is psi set. I usually do my own or I ask the guy to just walk them in and I break out a Tq wrench. They can make fun.

Lug brand, made out of weaker Al or inferior metals can't take the stress if not fully seated. Add in XX wheel brand w/o hub specific bore and NO hubcentric rings and you just elevated the wheel/hub/lug stress. Add in wider wheel widths over oem and up another notch. Certain wheel manufactures require certain lug styles, ball/seat, conical/acorn so I would pay much attention to that as well.

Very good scenario that you made out ok w/o harm to yourself or others. Better off this way analyzing here rather than the other way ... Scary for sure.

 

Makes me really nervous about the aftermarket wheels I just bought. They require "mini" lugs.

 

81 ft lbs is the factory spec.