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This subject has been thoroughly explored buy one of the major aluminum wheel manufacturers and the trucking industry because of the occurrence of medium truck "wheel-offs". Their results showed that these devices were not accurate and did not yield the intended torque. All wheel and tire manufacturers insist in their safety literature that a properly calibrated torque wrench be used to establish the proper lug nut torque and hence, wheel clamping force.

 

If it don't work for trucks, it don't work for cars. You'll save a lot of warped discs and broken studs if you use a torque wrench. An impact wrench, if used, should be set well below the final torque to allow the proper value to be achieved with a torque wrench.

 

Happy Holidays to all.

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Excuse me for hi-jacking the thread, but is a torque wrench really that necessary? Besides tightening head bolts or something that precise? I haven't used a torque wrench in YEARS, and have done a fair share of bolt tightening. I have never had one come loose, I haven't even broken a bolt in ages... Or do I just have a very good mechanic's feel?

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Originally posted by subyluvr2212

Excuse me for hi-jacking the thread, but is a torque wrench really that necessary? Besides tightening head bolts or something that precise? I haven't used a torque wrench in YEARS, and have done a fair share of bolt tightening. I have never had one come loose, I haven't even broken a bolt in ages... Or do I just have a very good mechanic's feel?

 

Having the torque on the wheel lug nuts and axle nuts is important for optimum wheel bearing life, but provided you use a 10-12 inch wrench you will get the desired 72-85 lb ft for the lug nuts.

 

I use my torque wrenches religiously, but many mechanics do not and the majority of the time no problems are encounter, but when overtorquing problems do occur the fix can be costly. You can develop a good feel for the appropriate torque, and can estimate within reason by adjusting wrench length. Knowledge of bolt size/grading is also recommended, since both affect torquing.

 

I am a bit of a torque nut since my hobby includes rock climbing where the proper torquing of rock bolts is required to avoid the possibly of slipped expansion sleeve (too little torque) or sheared bolt head (too much torque). Lives are on the line in these cases, but they are on the road too!

 

I have three torque wrenches, a high torque 1/2 drive, a medium torque 3/8 drive and a low torque 3/8 drive. I even go so far as to have them re-certified yearly, full-time mechanics should re-certify their torque wrenches far more often. Heavy truck mechanics are required to keep of log of there torque wrench calibrations and certifications.

 

BTW: when alloy wheels are torqued, they should be checked in about 1,000 km or a week since they can come loose due to the expansion/contraction of the alloy wheel. Typically new alloy wheels or alloy wheels coming out of winter storage will show signs of loose lug nuts a week or so after installation.

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Thanks for the replys, I had my doubts about them when I seen the tire people at Wal Mart who have torque sticks finish the job with torque wrenches. I have plenty torque wrenches already I just wanted a time saving device. The little lug wrench that came with my Subaru gets real close to the right torque when I get it about as tight as I can get it.

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The other problem with torque stiks is I think you have to stop the moment the stick starts to vibrate.

The last guy who installed my winter tires kept at it at least a couple of seconds after that moment.

Maybe someone more knowledgeable could straighten things out on this, but I think this negate the whole idea of the torque stick.

The vibration does'nt stop the torquing action (maybe it slows it down a little), it's just a sign to tell the operator that proper torque has been reached.

Am I wrong on this?

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A good friend of mine worked at Wal-Mart changing oil and tires to pay for college. Wal-Mart insisted on the use of these torque sticks for lug nuts, and he got into trouble for using a proper torque wrench instead because it took too long (like 2 minutes too long).

 

My Wal-Mart friend once worked with a new employee who could not get the huge combination oil drain/oil filter holder off of a GM Quad 4 engine. He used an impact wrench but instead of releasing the trigger when the drain/filter holder began to spin loose, he kept holding the trigger and spun the whole 4" diameter drain off the engine and 5 litres of oil promptly dumped on his head! Needless to say this co-worker did not last long....

 

I consider impact wrenches to be the tool of last resort if a bolt or nut does not come off, but I would never personally use one to reinstall any bolt or nut. Too many issues with over torqued and stressed bolts to deal with when impact wrenches are used.

 

Everytime my car is serviced and the tires are taken off I often find the lug nuts are at or above 125 lb ft, which is way off the 72 lb ft spec, and the itty bitty lug wrench included with the car will only work to release these overtight lug nuts if jumped on. In my case the worst offender was Subaru of Calgary who should have known better. I documented the problem and photographed my torque wrench settings to remove these bolts and sent a note to Subaru Canada. Subaru of Calgary sent me an apology letter and a complimentary oil change coupon, but I have to leave the car with them for the day so they can change the oil at their convenience instead of mine!

 

Merry X-Mas

:santa:

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I have had a torque wrench for years, but never thought about having it recalibrated.

 

On the one hand, is this necessary? After all, what can go wrong with the torque wrench. Mine relies solely on the bending properties of the arm (which moves a scale/pointer to show the torque). Other than a change in the material properties of the arm (extremely unlikely), I can't see what would make the torque wrench not keep reading correctly for ever.

 

On the other hand, I suppose it would be easy to check the calibration myself. I could hang a known weight at a fixed radius on the torque arm. Has anybody tried this?

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Originally posted by forester2002s

I have had a torque wrench for years, but never thought about having it recalibrated.

 

On the one hand, is this necessary? After all, what can go wrong with the torque wrench. Mine relies solely on the bending properties of the arm (which moves a scale/pointer to show the torque). Other than a change in the material properties of the arm (extremely unlikely), I can't see what would make the torque wrench not keep reading correctly for ever.

 

On the other hand, I suppose it would be easy to check the calibration myself. I could hang a known weight at a fixed radius on the torque arm. Has anybody tried this?

 

These are the inexpensive type which are also more difficult to get a correct torque reading, especially above 25 lb ft just at the point where it can be difficult to hold the tool steady under strain. After a while the metal arm will become less resistant to bending and your torque settings will be low. How long will this take? A long time but it will happen.

 

The better torque wrenches allow you to dial the handle to the desired torque and when the proper torque is reached the wrench will release and click. These type of torque wrenches can and should be calibrated every 2000 or so torque cycles (100 cars worth of wheel installations). The dial a torque wrenches cost between $50 and $500, which is far more than the needle/graph type, but they are far more accurate, much easier to use and more durable in the long run. With some of the lower priced dial a torque wrench you simply have the tool tested and if more than 5% out you toss the tool out and get a new one. They are usually good for several thousand torquings if treated properly. One drop and the tool is usually out of calibration. The problem is finding a place that can calibrate these tools. I found a place in Calgary that calibrates scales that can test the wrench for $3 and calibrate for another $4. Mine are tested every year and thus far I have only had to have one calibrate to correct a +2% error.

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Alais is talking some seriously good stuff here.

I would like to add

1) the "beam" style torques wrenches have limitations but given the broad band of torque quoted for lug nuts they are much better than no torque wrench. Shoot for the middle of the range.

2) Two very important places a good TW comes into focus that most people never even think of are

i) Spark plugs - too loose the can work out of the head - sometimes tearing the last couple threads out - bummer

Too tight and they can gaul in the head and be a real bugger to remove.

ii) Get this one!! - Oil pan drain plug. Too tight - can strip either plug or pan, too loose --well no need for explaination except for "Hey Ethel what is that ticking noise"--- WHACK

Make a torque wrench your friend, and one last addition about the calibration, (which is a very good idea) -

these "snap" type TWs work via a spring load, and as with all spring loaded devises, they are best left unwound.

When finsidhed with the TW set the dial back to zero, this will help keep it calibrated.

Hope this helps

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I'm with the folks who use them, definitely!

Besides the wheel bearings, there's one more issue I know of: brake rotors. Well, Subarus, being Japanese and therefore quality stuff, can probably take a lot of abuse, but still: regular overtorquing and especially not even torque on the lug nuts may cause the rotor to warp. I have never seen anybody in tire shops running around cars with torque wrenches, so I just give them wheels -- without the car. If they screw up balancing, no big deal.

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I used the torque sticks at ivy thech. the idea is the stick will twist and absorb the hammering effect of the impact, therefore limitong the amount of torque being trensferred before the twisting acts as a shock absorber for the impact.

there was a color code, and you looked up the year and lug pattern, make, model, it told u which color to use

 

i have used the bar type torque wrenches onmy head gaskets.

i did roberts spfi, the trashwagons ea81, and both ea82's, and my turbo without reliability issues.

(both my ea82's withstood a mild overheat with new gaskets installed)

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  • 2 years later...

Someone was asking about Alias 20035, so I went back to some of his post and found this topic I started about torque sticks, I would like to say I went on to buy these sticks even with so many saying they are not accurate, I found them to be very accurate. I have had these for a few years now and used to check them with a torque wrench but now I trust them to be within a couple of ft. lbs. so I dont even check them anymore. However it might just be the right compresser and impact wrench that is making it correct, and they very well may not be as accurate on another system.

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