# Correct Wheel Torque Settings?



## MC (May 22, 2002)

The manual indicates 72lb-ft. Does this apply to all type of wheels? I own a 2002 325i w/ SP 17-inch alloy wheels. Do you follow the factory recommended settings?


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## Mr. The Edge (Dec 19, 2001)

88 ft-lbs is the new recommendation


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## MC (May 22, 2002)

And I just bought a Sears torque wrench with 5-80 ft-lb of settings:banghead: Thanks for the info.


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## nate (Dec 24, 2001)

MC said:


> *And I just bought a Sears torque wrench with 5-80 ft-lb of settings:banghead: Thanks for the info. *


It is +/- 10Nm, so you are still in the acceptable range....


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## CMOS (Oct 1, 2002)

MC said:


> *And I just bought a Sears torque wrench with 5-80 ft-lb of settings:banghead: Thanks for the info. *


What sorts of connectors do torque wrenches have? Are they basically socket wrenches and therefore take any standard socket pieces?


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## Chris330Ci (Jan 23, 2002)

CMOS said:


> *
> 
> What sorts of connectors do torque wrenches have? Are they basically socket wrenches and therefore take any standard socket pieces? *


Yes, they take standard sockets, but of course, it depends on what size drive you have. 3/8", 1/2"...


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## berford (Sep 10, 2002)

Chris330Ci said:


> *
> 
> Yes, they take standard sockets, but of course, it depends on what size drive you have. 3/8", 1/2"... *


It also depends on the size of the opening. Some wheels require a thin walled socket--the SSR GT1s I currently have on, for example...


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## SchwartzBlack (Jan 4, 2002)

Do I need to tighten it more for steel wheels (my winter setup)? The mechanic claims that it should be 90lb for steel and 72lb for alloys?


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## Magna (Jan 4, 2002)

SchwartzBlack said:


> *Do I need to tighten it more for steel wheels (my winter setup)? The mechanic claims that it should be 90lb for steel and 72lb for alloys? *


good question!! also heard something simliar


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## Artslinger (Sep 2, 2002)

I use 88 ft-lbs on both the steel and the alloys. Someone told me thats it a good idea to re-torque new steel wheels after about 100 miles.


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## AF (Dec 21, 2001)

MC said:


> *And I just bought a Sears torque wrench with 5-80 ft-lb of settings:banghead: Thanks for the info. *


return it back to sears and get another one . . .sears has a great return policy . . . they pretty much take anything back


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## SchwartzBlack (Jan 4, 2002)

Well if the new spec calls for 88lb/ft on the alloys, it should then 88lb should work fine for steel wheels too. I do re-torque my wheels a month or so after putting them on, but they've always been tight. So it would seem like a waste of time.


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## Gs330Ci (Feb 4, 2002)

What size socket is required for the lugs on sport package wheels? I need to get one. I have a torque wrench, but not the correct size socket.


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## Llarry (May 17, 2002)

17mm. A deep socket will bring the wrench out so that bodywork does not interefere with the swing of the wrench.


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## berford (Sep 10, 2002)

LMC said:


> *17mm. A deep socket will bring the wrench out so that bodywork does not interefere with the swing of the wrench. *


Good point/warning--I torqued one bolt before realizing this. If you don't have an extension, you need to keep the wrench low relative to the body. Otherwise it's very easy to hit the fender.


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## Ausgang (Jan 4, 2002)

*Be careful how much faith you put into 'Torque'*

RE:
* (1) I do re-torque my wheels a month or so after putting them on, but they've always been tight. So it would seem like a waste of time . . . . (2) The torque for steel wheels should be the same as for alloy . . . . (3) it's =+/-10Nm so you're within range. . . . 

OK, let's add some clarity to what's going on here. 'Torque' is a measure of lever-arm turning resistance. Tension (clamping force) is what is needed to keep the wheels on. The relationship between the two is 'indirect', meaning correlated though not dependent.

The torque-tension relationship is NOT a linear relationship. (Even OEMs rarely grasp this.) Under Ideal Laboratory Conditions, an OEM can correlate a given 'torque setting' to within +/- 30% of the design engineer's targeted tension for a connection. In the real world (like when we're installing wheels on our cars) the relationship between torque and tension is closer to +/-50% with 95% confidence.

Facts: The majority of 'torque' applied to tighten is consumed by frictional and geometric factors related to each individual fastener and connection. This energy dissipates as heat. Only about 10% of your torsional energy is converted to potential energy of tension in the fasteners --- which is what holds the wheels on.

With respect to some of the posts:

(1) Re-torque requirements: When an OEM asks that a re-torque procedure be followed, it is because they are aware of some 'joint relaxation' which may occur early on as thick paints, soft interfaces, and other factors lead to some loosening. When such a requirement is called out, the fastener MUST first be loosened and then tightened to the specified level. This is because the initial torque needed to put a fastener into motion is significantly greater than that required to keep it in motion. Thus, a torque wrench 'inspection' of already tightened fasteners will not move them unless an initial peak of ~40% higher torque is applied. Failure to recognize this fact leads to assuming the fasteners are tight when they may not be, and potential for subsequent fatigue failure.

(2) The torque for steel will NOT be the same for alloy if any part of the fastener is in contact with any bearing surface on the wheel. The differences can only be learned by experimentation with sophisticated equipment. There are no simple 'factors' that can be reliably applied. Note that this means people who install aftermarket wheels should rely on the wheel supplier's specs, no longer the OEMs. (which is applicable only to the stock wheels.)

(3) When the OEM says the torque tolerance is +/-10% what they are really saying is that the accuracy of the tool need only be calibrated to that accuracy, not that you can 'select' a torque withing that range. In effect, the OEM is prohibiting the use of most air-impact wrenches because they can not be calibrated to this level of accuracy. Most mechanics hand torque wrenches (Craftsman, MAC, Snap-On, etc. are calibrated to an ANSI standard which requires full-scale accuracy to +/- 4%.

Lastly, it is imperative that all threaded fasteners be installed having a surface finish identical to that recommended by the OEM. Even substitution of a different lubricant or use of a plated fastener for a plain finish one will invalidate the torque/tension relationship for a given connection.

There, now you guys know more than half the engineers I have to train.*


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## berford (Sep 10, 2002)

Very educational, Ausgang. Thanks a bunch.:thumbup:


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## AF (Dec 21, 2001)

Great post Ausgang . . . thank you for taking the time to teach us:thumbup: :thumbup:


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## SchwartzBlack (Jan 4, 2002)

Wow, thanks Ausgang. 

For (2) would you say that in general that the torque required for steel wheels is greater than that for alloys or are there too may variables to make that generalization?

I've never used a lubricant on my lug bolts. Should I? 

thanks again


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## abqhudson (Dec 22, 2001)

*88 ft-lbs for wheel lugs for e46 sedan is NOT CORRECT.*

According to my local BMW Service Manager, 88 ft-lbs is an urban legend - shows that folks will believe anything they read on the internet. If he is wrong, please advise as to the official BMW reference.

Jim


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## CMOS (Oct 1, 2002)

*Re: 88 ft-lbs for wheel lugs for e46 sedan is NOT CORRECT.*

Page 144, "Changing a wheel", Col. 2, para. 3 in my 2003 330i Owner's Manual (the one that comes with the car):

"torque specification: 88.5 lb ft/120 Nm"

Some folks will believe anything they read in the manual!



abqhudson said:


> *According to my local BMW Service Manager, 88 ft-lbs is an urban legend - shows that folks will believe anything they read on the internet. If he is wrong, please advise as to the official BMW reference.
> 
> Jim *


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## e46shift (Oct 12, 2002)

*Re: Re: 88 ft-lbs for wheel lugs for e46 sedan is NOT CORRECT.*



CMOS said:


> *
> Some folks will believe anything they read in the manual!
> 
> *


:lmao:


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## Artslinger (Sep 2, 2002)

*Re: 88 ft-lbs for wheel lugs for e46 sedan is NOT CORRECT.*



abqhudson said:


> *According to my local BMW Service Manager, 88 ft-lbs is an urban legend - shows that folks will believe anything they read on the internet. If he is wrong, please advise as to the official BMW reference.
> 
> Jim *


From my personal experiences... don't believe everything a BMW service manager tells you.


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## abqhudson (Dec 22, 2001)

*Thanks for the correction.*

Based on the new information - 2003 Owners Manual - my local BMW Service Manager now says that the new torque specification of 88 ft-lbs applies to all e46 cars. Thanks for the help.

Jim


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