Wheels' Lug nuts loosened unexpectedly

Art wrote:
> When was the last time you had your torque wrench calibrated?
========

Doesn't calibrating a torque wrench cost as much as buying
a new one?

This Sears Craftsman's cost $80, which is about the
price of calibration, I think.

RT wrote:
>
> I was just going to say, is it the same torque wrench ?
> Has it been properly stored ? Used a lot in between ?
=======

Yep, it's the same torque wrench, stored with the numerical
torque selector at the lowest setting, as Tegger
recommended, contrary to the Sears salesman who recommended
storing at 20 foot-pounds. IIRC the salesman said there was
some memo floating around recommending that the Craftsman torque
wrenches be stored at 20 foot-pounds to prevent damage to the
mechanism, but I think Tegger is probably right, and have
stored my wrench at zero Newton-meters ever since.

It is interesting, though, that almost all the torque wrenches
I've seen at Sears (and the Huskys at Home Depot and the Kobalts
at Lowe's) have all been set to a torque of between 20 and 30
foot-pounds while they're sitting on the shelf waiting to
be bought.

But I have faith in Tegger, and store my wrench at zero.

E Meyer <epmeyer50@msn.com> wrote in
news:C4A64384.32ACC%epmeyer50@msn.com:

>
>
>
> On 7/18/08 10:44 AM, in article
> 81b8786d-92f6-4e56-87bc-d712c650b609...oglegro,
> "Built_Well" <Built_Well_Toyota@m> wrote:
>
>> RT wrote:
>>>
>>> I was just going to say, is it the same torque wrench ?
>>> Has it been properly stored ? Used a lot in between ?
>> =======
>>
>> Yep, it's the same torque wrench, stored with the numerical
>> torque selector at the lowest setting, as Tegger
>> recommended, contrary to the Sears salesman who recommended
>> storing at 20 foot-pounds. IIRC the salesman said there was
>> some memo floating around recommending that the Craftsman torque
>> wrenches be stored at 20 foot-pounds to prevent damage to the
>> mechanism, but I think Tegger is probably right, and have
>> stored my wrench at zero Newton-meters ever since.
>>
>> It is interesting, though, that almost all the torque wrenches
>> I've seen at Sears (and the Huskys at Home Depot and the Kobalts
>> at Lowe's) have all been set to a torque of between 20 and 30
>> foot-pounds while they're sitting on the shelf waiting to
>> be bought.
>>
>> But I have faith in Tegger, and store my wrench at zero.
>
> The users manual that came with my Home Depot wrench specifically said
> to store it set to 25 foot-pounds and specifically warned against
> storing it at zero.
>
>

The manual that comes with my Sears MicroTork says this:
"When the wrench is not in use, keep it set below 25% of capacity. If you
leave the wrench set at a reading of more than 50% capacity for more than a
few hours, set the wrench at its lowest setting and leave it there for a
few minutes before using it again."

I infer from this that the lower the storage setting the better, although
benefits of storing at 0% capacity are apparently not significantly greater
than storing at 24%.

Since it's clearly being left to me to decide between 0% and 24% as I see
fit, I see fit to impose zero deformation on the spring in my torque wrench
rather than some deformation. Except for, of course, the danger that I may
loosen that famous locknut unless I'm very careful or stop turning a click
or three short of the bottom...

--
Tegger

"Ray O" <rokigawaATtristarassociatesDOTcom> wrote in
news:IfqdnZVLvYsdkh3VnZ2dnUVZ_rvinZ2d@:

>

>
> Were the wheel on the ground when you did the final tightening?

Exactly what I was wondering.

I don't think final tightening should ever be done with the entire weight
of the car bearing on the wheels.

I drop the car so the wheels are pressed into the pavement just enough to
keep them from turning and no more. Assuming I'm working on wheels with no
way of locking them mechanically, that is.


>
> Was the wheel properly seated before lowering the vehicle to the ground?

I've never personally seen rust or aluminum corrosion cause wheel nut
loosening (although the pro's here may have different observations...).
I /have/ seen rust or corrosion cause odd clicking noises at the wheels
when going around tight, slow turns.

--
Tegger

Retired VIP <jackj.extradots.180@windstream.net> wrote in
news:iti18411mt7sf6nnfkf98o5bf4t7hrqe86@:


>
> You need to be sure that the shoulder of the nut is seated properly
> into the counter-sunk lug hole of the wheel.

One thing I'd caution is to make sure the nuts are properly mated to the
wheel. When people start swapping and mix-matching OEM for/with
aftermarket, some odd and non-functional combinations can occur. Not saying
Built_Well is doing this, but just in case...

A case in point is a neighbor of mine who obtained a set of wheels and a
set of chrome nuts from separate sources. Well. The wheels had a
45-degree shoulder on the nut seating surfaces, but his new wheel nuts had
what appeared to be a 60-degree seating surface.

My neighbor came to me saying the wheels kept loosening up on him, and what
could I do to fix it? I made some basic checks, found the mismatch and said
he should get the proper nuts, even if they were cheapo non-chrome ones. He
insisted he had no time and had to get where he was going, so I tried to
torque them up for him. Believe it or not, they did eventually reach proper
torque, but it was obvious the wheel hole shoulders were deforming in order
to achieve this. I told him I wasn't sure how well this was going to work,
so to be careful as he drove.

They came loose again in about an hour's driving.

--
Tegger

Built_Well wrote:
> Art wrote:
>> When was the last time you had your torque wrench calibrated?
> ========
>
> Doesn't calibrating a torque wrench cost as much as buying
> a new one?
>
> This Sears Craftsman's cost $80, which is about the
> price of calibration, I think.

A local place did mine for about $40.

I was informed new torque wrenches can be off by 15%.

FWIW, I've owned a lot of cars, and have had two cars that were absolute
sticklers and PITA's for loose lug nuts. Most of them you could do
wheel nuts by feel and never worry, but my Jimmy and my old old Buick if
you didn't torque 'em proper and then recheck the next day, the SOB's
would work loose.

You might have one of "THOSE" cars where every time you take the wheels
off you'll have to check the torque a couple of times.

Ray

On Jul 19, 8:53 pm, ray <rollingviolat...@domain.invalid.com> wrote:

> > Doesn't calibrating a torque wrench cost as much as buying
> > a new one?
>
> > This Sears Craftsman's cost $80, which is about the
> > price of calibration, I think.
>
> A local place did mine for about $40.
>
> I was informed new torque wrenches can be off by 15%.

Easily. I bought two US-made Husky torque wrenches and the
calibrating guys had to work on them for some time to get them
anywhere near accurate. Cost more than the wrenches. And that's for
good wrenches, not the cheap stuff found in some places now. Sears
here in Canada sells Chinese-made tools, has been for a long time,
while Sears in the US might still be selling better US-made wrenches.
Dunno. Cheap wrenches, at any rate, could be 30% off and have very
poor repeatability, giving a different torque every time the wrench is
set to zero and then back to the desired setting.

Dan

"C. E. White" <cewhite3@> wrote in message > I am of the
opinion that the beam type wrenches are inherently accurate.
> They are unfortunately inconvenient to use. What I have done in the past
> was to use a beam type wrench to check my click type wrench. Maybe a fools
> idea, but so far, nothing has fallen off. And actually it should
> relatively easy to check any torque wrench with weight applied at the
> handle by a string. Never tried it though.

I believe I have seen setups where deadweights are used to calibrate the
torque wrench.
This is what I would use, if I were going to calibrate one, since an
accurate deadweight
is a reproducible standard.

For a lot of applications, extreme accuracy of the torque wrench may not be
totally necessary, if the evenness of adjustment of the clamping force is
more important than
the absolute magnitude of the force.

Still, most of us would not want to pay money -any money - for what is
supposed to be
a precision tool, only to get something that is embarassingly imprecise.

Maybe we could get some car magazine (or even Consumer Reports) to do
a series on this?

Yeah, don't torque with load on the wheels, at least before reaching
60 lb/ft. That puts "side-loads" on them. Better yet, avoid even
partial loads until reaching 60 lb/ft.

On Jul 19, 12:03 am, Built_Well <Built_Well_Toy...@m> wrote:
>
> By the way, the author of the book "Auto Upkeep" also torques
> his wheels while they're just barely touching the ground--touching
> just enough to prevent wheel movement.
>
> However, the author neglected to mention not to torque your wheels
> while they're hot.  Luckily, I read at TireRack.com the
> following:
>
> "When rechecking torque value, wait for the wheels to cool
> to ambient temperature (never torque a hot wheel)."  [Sounds
> like a good idea.  But does anyone know why?]
>
> Here's a longer passage from TireRack.com :
>
> "When installing new wheels you should re-torque the wheel lugs
> after driving the first 50 to 100 miles in case the clamping
> loads have changed following the initial installation. This is
> necessary due to the possibility of metal compression/elongation
> or thermal stresses affecting the wheels as they are breaking in,
> as well as to verify the accuracy of the original installation.
> When rechecking torque value, wait for the wheels to cool to
> ambient temperature (never torque a hot wheel).  Loosen and
> retighten to value, in sequence. Simply repeat the same torque
> procedure listed above."