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Discussion Starter · #1 ·
After lurking around for a while I'm now finaly having a problem with my 9k.

The problem is with the wheel bolts. They are tightening themselves up. Had the car in a garage 2 months ago for mot repairs and they had a lot of trouble removing the wheel bolts. They mentioned this and said they torqued the wheels up to 80n/m.

Two weeks ago I had to replace the front disks and pads and I couldn't get the wheels off, shearing two 1/2" drive socket set extension bars. I ended up borrowing some heavy duty kit from work with a 4 foot scaffold tube and a 22 stone friend to release the wheel bolts, this did the trick. Once the tension is released the bolts are free to undo by hand. Two days after I replaced the disks I checked the bolts again and had trouble releasing them, too tight again.

Wheels are 16" Aero's.

Any idea's?

Thanks in anticipation
 

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Heh, it's very amazing to see how technician at wheel change station is jabbering with a pneumatic screw-driver-gun for almost 10mins to release one bolt..., then another.... And at the next wheel change - again... It's somehow typical to Aero rims I guess
 

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It's a common problem to all alloy wheels... if you're really "lucky" they'll also stick to the hub too... It's caused by electrolysis resulting from different electronegativities blah chemistry blah

I've used Copper Ease on my wheel bolts AND the face betweeen them and the hub for years now and never had any problems. It says on the tube/can that it's also suitable for wheel bolts. In fact I use it quite widely as a general anti-sieze measure.
 

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I've never had this happen on my Aero rims as long as I torque them myself. However, I have had tyre shops do them up extremely tight. When I had new tyres fitted a week ago, I drove straight home and checked the bolts. On one wheel, I had to take my 30" long torque wrench (the one I use for driveshaft nuts) and stand on the end! I reckon it took around 250-300 lbft to shift them. Strange, as they used the same tool on all the wheels. The tyre pressures were also all over the place.

I do use copper grease on the bolts. I've never seen any recommendation to the contrary. I'd be interested to hear why it's a bad idea.
 

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I was always taught that any bolt that was to be torqued up should be "lightly oiled". Never had a wheel come off, although you should re-torque after the first decent drive.

Since my alloys seized on the hub last month I've slapped copperease everywhere and the wheels are still on after 2,000 ml.
 

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Discussion Starter · #8 ·
Thanks for the replies.
I do use copperslip on the threads and back of the wheels, had them stick on another car I used to have. Once the bolts are loosened they can be undone by hand.
I am starting to think that it may be pick up between the two metals on the tapered shoulder section on the bolt.

I still have the scaffold tube for emergencies.
 

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I put copperease on the tapers as well. Haven't undone them yet, but the bolts weren't seized, only the wheels.

One other thought on your problem. Are you on standard wheels? have you got after market locking bolts? If the spec is out a bit, the end of the bolts might be running out of thread. Haven't got a 9000 and haven't looked at mine on the 9-5 so I might be talking rubbish (again
).
 

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Definately recommend copper grease between alloy and hub. Never had a need to use them on bolts though. Stretched boths (due to overtightening) should be replaced!

Overtorquing wheel bolts can stretch the bolts and also damage the alloys. I have come across several garages of late who use the hydraulic torque gun to put the nuts on lightly, then a torque wrench to hand finish the job off.

Not sure if this is now a legal requirement, or whether they are seeking to protect themselves from liability should wheel bolts snap, etc.
 

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I use Copper Slip grease and torque them to the recommended 75 lbft. Never had a problem unless some of these monkeys at tyre fitting establishments have been near them.
If the bolts are too long, like alloy wheel bolts with a steel wheel, then the extra thread will project out the back of the hub where it will pick up dirt and corrode with possible difficulty in unscrewing in the future.
 

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Discussion Starter · #13 ·
I'm open to all theories at the moment.

After a run up to Blackpool at the weekend, last night, I tried to loosen the bolts and found that 6 needed the scaffold tube to release them, four at the front and two at the rear. Today I bought a torque wrench. This will enable me to keep a more accurate check on the tightness. I will check the bolts again in a coulpe of days.

Thanks for the replies.
Keep you posted

Keith
 
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