GM / General Motors: 02 GrandAm brake rotors

Do you mean oversized holes where the studs go through, or the centre hole
is oversized? The centre hole should not be, but the holes for the studs
should....and no, it doesn't matter. As long as the rotor, hub, and wheel
are clean when they are installed, the clamping pressure from the five lug
nuts will be more than sufficient to hold the brake rotor in place.

T = KDP

1200in*lbs = (.20)(.5")P
P=12,000lbs/lug nut

P = 12,000lbs*5 lug nuts = 60,000lbs clamping force

Steve

"Eldon Jons" <net> wrote in message
newsublic.lawson.webtv.net... 


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Are they over torqueing when switching wheels?

"Steve Mackie" <sympatico.ca> wrote in message
news:M0qkb.17660$nbnet.nb.ca... 

That would be my suspicion as well - problems often seem to result from this
on these cars, if they are gunning the lug nuts on with an air gun without
regard for torque, the rotors can warp when they heat up.

--
Robert Hancock Saskatoon, SK, Canada
To email, remove "nospam" from ca
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"Tj" <rr.com> wrote in message
news:ZwHkb.34793$nyroc.rr.com... 
hole 
wheel 
lug 
would 
brakes 

Especially if there is dirt/rust on the rotor/hub/wheel and if they do not
tighten the lug nuts in the roper order.

Steve

"Robert Hancock" <ca> wrote in message
news:_jJkb.132508$.. 
this 
studs 
the 



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Robert Hancock wrote: 

Do you know what the torque specs might be?

My g/f's Alero is notorious for warping rotors at the rate of an oil-change.


-marc

100 foot-pounds. They're also supposed to be tightened in a star pattern.

My guess would be that uneven torque on the lug nuts would be even worse
than overtorquing..

--
Robert Hancock Saskatoon, SK, Canada
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Home Page: http://www.roberthancock.com/


"Marc Westerlind" <com> wrote in message
news:com... 
this 
without 
oil-change. 

Robert Hancock wrote: 

Cool, that's about what I guessed. Last time I had the wheels off,
I just cranked them on "fairly" tight... definitely in a cris-cross
star pattern. I didn't think the torque mattered that much.

I'll be sure to pull out the torque wrench when I get the rotors
turned.

Thanks,
-marc

At the dealerships these days, they use torque sticks. It's an attachment
that goes onto an impact gun. The gun will jump when the proper torque has
been achieved. And,... it will go no farther.

If you don't torque the lugs evenly, your rotor can warp.

Just because you saw them use an impact gun, when they tightened the lugs,
it doesn't mean that they did it wrong. If you see a 6" to 8" extension on
the gun, they are doing it correctly.

GMdude.

P.S. Unless you purchase a torque stick for your impact at home. You should
use a torque wrench to tighten your lug nuts.