Torque Wrench vs Torque Sticks for wheels?

[10thanncobra]

Im kind of laughing at this also out the shops Ive worked in,between 14 techs, me and only one other I ever saw torqued a wheel. gun and run lol

 

[czgunner]

Always torque stick.

 

[Notgrownup]

I usually torque mine after the shop.

 

[tekgmr]

So .... I didn't read through all the comments and don't know if this has been pointed or not.

A torque stick is designed to limit the torque of your gun to prevent over torquing. Not to act as a device designed to set specific torque. It might get it close but they're pretty unreliable. Always use a torque wrench.

Sent from my LG-H901 using Tapatalk

 

[WhiffySpark]

Funny how only the backyard arm chair mechanics have problems with torque sticks. In which they most likely have 0 experience with

 

[WhiffySpark]

2 min per car X 10 cars per day, 20 min per day.

20 min per day X 5 days per week, 100min per week, 1 hour and 40 minutes.

100min per week X 52 weeks per year, 5200 min per year, 86.6 hours, 3.61 DAYS per year.


3.6 DAYS.



I used to use hand tools. Now air/electric is used on anything within reach. Time, time, time, time, time. Time, it's all I got to sell, so making the most of it when there's more work waiting matters.

That's few thousand dollars for me. The little stuff adds up

 

[Adam.C]

2 min per car X 10 cars per day, 20 min per day. 20 min per day X 5 days per week, 100min per week, 1 hour and 40 minutes. 100min per week X 52 weeks per year, 5200 min per year, 86.6 hours, 3.61 DAYS per year.

How much do your cigarette breaks cost you?
How would you feel if your surgeon said the same thing? Or the carpenter who built your house?

 

[BrokewrenchLS1]

2 min per car X 10 cars per day, 20 min per day.

20 min per day X 5 days per week, 100min per week, 1 hour and 40 minutes.

100min per week X 52 weeks per year, 5200 min per year, 86.6 hours, 3.61 DAYS per year.


3.6 DAYS.



I used to use hand tools. Now air/electric is used on anything within reach. Time, time, time, time, time. Time, it's all I got to sell, so making the most of it when there's more work waiting matters.

I'm sure you don't spend the equivalent of 3.6 days slugging coffee or bullshitting with other mechanics during the year, right?

Who needs to do the job right when that takes time? This thread pretty well reinforces why so many people think of mechanics as nothing but hack crooks.

 

[BrokewrenchLS1]

Funny how only the backyard arm chair mechanics have problems with torque sticks. In which they most likely have 0 experience with

Funny how people with mechanical and engineering degrees are explaining why torque sticks shouldn't be considered an acceptable substitute to a torque wrench, but hacks - sorry, mechanics - completely ignore those facts.

 

[BK13]

I'm an amateur. I'll use a torque wrench.

Me too. I run the lugs down with my M18 impact wrench on setting 1, then follow up with a torque wrench.

 

[bmwpowere36m3]

Funny how people with mechanical and engineering degrees are explaining why torque sticks shouldn't be considered an acceptable substitute to a torque wrench, but hacks - sorry, mechanics - completely ignore those facts.

There's a difference between sitting behind a desk and in front of a textbook vs. reality. I know, by profession I'm a mechanical engineer for a helicopter manufacturer. My father is a mechanic and been so 30+ years. I learned a lot from him growing up and car/motorcycles are my hobby, not career.

The same can be said for torque wrenches, as far as accuracy... torque is a terrible indicator or bolt tension or preload. However for most applications its more than good enough. So maybe a torque stick is not accurate, but is it accurate enough?

I work with mechanics in the hangar all the time and they certainly don't use a torque wrench for every nut/bolt, even though they all have specs. Critical fasteners, yes. Sometimes you have to say, its good enough.

 

[BrokewrenchLS1]

There's a difference between sitting behind a desk and in front of a textbook vs. reality. I know, by profession I'm a mechanical engineer for a helicopter manufacturer. My father is a mechanic and been so 30+ years. I learned a lot from him growing up and car/motorcycles are my hobby, not career.

The same can be said for torque wrenches, as far as accuracy... torque is a terrible indicator or bolt tension or preload. However for most applications its more than good enough. So maybe a torque stick is not accurate, but is it accurate enough?

I work with mechanics in the hangar all the time and they certainly don't use a torque wrench for every nut/bolt, even though they all have specs. Critical fasteners, yes. Sometimes you have to say, its good enough.

What I've always been told about torque wrenches is that without knowing a lot of other variables - materials, surface treatment (antiseize, thread locker, etc), they're more for consistency and rough order of magnitude torque than anything else. Critical applications (that I've seen) always use torque + angle, or TTY fasteners. I've also seen some torque-indicating fasteners, but not often (mostly outside the scope of what I test). That said, a torque wrench is going to remove a lot of variables torque sticks create, but even using torque sticks is better than the "crank 'em on with the impact and call it good" method.

I'm not a torque nazi, but the mentality of "blast them on with an impact gun and call it good because I'm too busy to be arsed with doing it right" is...questionable. Lug nuts are easy to get close enough by hand, but when you're hammering them on with an impact capable of 650lb-ft torque and disregarding the problems that can cause "because I just don't have the time for that" when the alternative method of doing it correctly takes less time than it does to take a piss, it goes beyond just being lazy and borders on incompetence.

 

[BDT/NWMN]

What I've always been told about torque wrenches is that without knowing a lot of other variables - materials, surface treatment (antiseize, thread locker, etc), they're more for consistency and rough order of magnitude torque than anything else. Critical applications (that I've seen) always use torque + angle, or TTY fasteners. I've also seen some torque-indicating fasteners, but not often (mostly outside the scope of what I test). That said, a torque wrench is going to remove a lot of variables torque sticks create, but even using torque sticks is better than the "crank 'em on with the impact and call it good" method.

I'm not a torque nazi, but the mentality of "blast them on with an impact gun and call it good because I'm too busy to be arsed with doing it right" is...questionable. Lug nuts are easy to get close enough by hand, but when you're hammering them on with an impact capable of 650lb-ft torque and disregarding the problems that can cause "because I just don't have the time for that" when the alternative method of doing it correctly takes less time than it does to take a piss, it goes beyond just being lazy and borders on incompetence.

Yes, torque stick is better than just an impact wrench, but not as good as a torque wrench..... If People would refer to torque sticks as "Torque Limiting Sticks" the name would explain itself a bit more clearly. They are intended to limit over torque...

 

[bmwpowere36m3]

What I've always been told about torque wrenches is that without knowing a lot of other variables - materials, surface treatment (antiseize, thread locker, etc), they're more for consistency and rough order of magnitude torque than anything else. Critical applications (that I've seen) always use torque + angle, or TTY fasteners. I've also seen some torque-indicating fasteners, but not often (mostly outside the scope of what I test). That said, a torque wrench is going to remove a lot of variables torque sticks create, but even using torque sticks is better than the "crank 'em on with the impact and call it good" method.

I'm not a torque nazi, but the mentality of "blast them on with an impact gun and call it good because I'm too busy to be arsed with doing it right" is...questionable. Lug nuts are easy to get close enough by hand, but when you're hammering them on with an impact capable of 650lb-ft torque and disregarding the problems that can cause "because I just don't have the time for that" when the alternative method of doing it correctly takes less time than it does to take a piss, it goes beyond just being lazy and borders on incompetence.

I mostly agree, but the discussion is too black/white... would you call a mechanic incompetent because he didn't use a torque wrench for every fastener that has a torque spec? Where do you draw the line...

Experiences shape people's opinions... so for me, a torque stick on a the same gun has been checked and always within a couple pounds of 80 ft-lbs. Works for us.

Just like certain tool purchases from Harbor Freight have also been positive in my experience... so YMMV

 

[BrokewrenchLS1]

I mostly agree, but the discussion is too black/white... would you call a mechanic incompetent because he didn't use a torque wrench for every fastener that has a torque spec? Where do you draw the line...

Nope, I wouldn't. There are plenty of fasteners on cars that have a specified torque where it's not necessary.

However, in a situation where over-torquing a fastener can lead to known problems (warped rotors, seized lug nuts, snapped and sheared wheel lugs), willfully continuing to do something incorrectly on the basis of "I've never had anyone come back and complain about it!" or "It takes too long and time is money!", I'd be very tempted to call into question other practices of the mechanic that does it. If a mechanic can't do something as simple as torquing lugs correctly (because it might take 2 whole extra minutes per vehicle), why would I have any reason to believe he'd do any other repair any differently, especially if doing it right took more time than doing it wrong?

It's a mentality issue; yes, I understand the ******** flat-rate system drives that mentality, but that doesn't recuse the mechanic from owning the fact that he's doing something wrong, regardless of his excuses.

 

[ibedayank]

I am hourly so doing it right the first time does not cost me a dime... now redoing the job if I screw it up does. Flat rate is just an excuse to cut corners to save time not so much do the job right!!!

 

[WhiffySpark]

And hourly is an excuse to be lazy and take your sweet *** time doing anything.

 

[2ndGearRubber]

I'm sure you don't spend the equivalent of 3.6 days slugging coffee or bullshitting with other mechanics during the year, right?

Who needs to do the job right when that takes time? This thread pretty well reinforces why so many people think of mechanics as nothing but hack crooks.

Wheel doesn't fall off, studs/lugs aren't damaged. IE: Job done right. When I do occasionally torque wheels (upon customer request), I'm pretty close.




Mechanics are essentially independent businesses, hired by the shop. Each tech is paid a portion of the ticket (commission/flat rate/etc.). The shop is buying my time, and reselling it at a higher cost. My time, my rules.

Things that are actually torque sensitive, get torqued properly with a calibrated wrench. TTY bolts get replaced, gaskets get RTV on steep angles, etc. When skipping steps changes the performance of a component, one cannot skip those steps.



A wheel can be attached with a range of 70-200 ft.lbs, with no change it performance (ie; falling off). A lug nut is not nearly as torque sensitive as people make it out to be. It's an M12 stud guys, and it's not made of pot metal.

Same as a drain plug, or an oil filter. Yes, specs exist. People who do this 40+ hours a week, for years, are familiar with the torque involved. An m8 bolt has a general torque, between ALL makes/models, excluding torque to yield fasteners, for example. Lugs are no different.

 

[2ndGearRubber]

I'm not a torque nazi, but the mentality of "blast them on with an impact gun and call it good because I'm too busy to be arsed with doing it right" is...questionable. Lug nuts are easy to get close enough by hand, but when you're hammering them on with an impact capable of 650lb-ft torque and disregarding the problems that can cause "because I just don't have the time for that" when the alternative method of doing it correctly takes less time than it does to take a piss, it goes beyond just being lazy and borders on incompetence.

Who is advocating for 650? Guns have variable triggers for a reason.

ZING (sends the nut down the threads to contact the mating surface), Brap brump, tightens it within reason. Like, 100ish.

 

[2ndGearRubber]

And hourly is an excuse to be lazy and take your sweet *** time doing anything.

When working hourly, I can't say I was necessarily lazy. But I will work myself to death, making the money in MY pocket.

 

[whateg01]

...

A wheel can be attached with a range of 70-200 ft.lbs, with no change it performance (ie; falling off). ...

Might not fall off, but at 200 ft-lbs, it can be a little tough to break loose with a 4-way on the side of the road, especially if Grandma's the one on the side of the road. Combine over torqued with rusty studs and nuts, and you start to see a lot of broken studs.

Dave

 

[BrokewrenchLS1]

Wheel doesn't fall off, studs/lugs aren't damaged. IE: Job done right. When I do occasionally torque wheels (upon customer request), I'm pretty close.

Warped rotors or warped hubs while driving, seized lug nuts or snapped lugs the next time the tire comes off. No chance for damage, right?

Who is advocating for 650? Guns have variable triggers for a reason.

ZING (sends the nut down the threads to contact the mating surface), Brap brump, tightens it within reason. Like, 100ish.

Have you ever actually measured the torque applied at that gun setting?

I've had to replace a $250 set of rotors because a ******* blasted lugs on with an impact, so I tend to be a bit more careful with lug nut torque.

 

[WhiffySpark]

Warped rotors or warped hubs while driving, seized lug nuts or snapped lugs the next time the tire comes off. No chance for damage, right?



Have you ever actually measured the torque applied at that gun setting?

I've had to replace a $250 set of rotors because a ******* blasted lugs on with an impact, so I tend to be a bit more careful with lug nut torque.

Studs do not snap because of over torque when removing. They snap because someone cross threaded it when they put it on. Big difference

I don't buy the warped hub or rotor argument either. It's just not logical for a lugnut to be able to warp a rotor

 

[WhiffySpark]

And most guns don't have 650 ft lbs of FORWARD torque. That's reverse torque.

 

[BrokewrenchLS1]

Studs do not snap because of over torque when removing. They snap because someone cross threaded it when they put it on. Big difference

I don't buy the warped hub or rotor argument either. It's just not logical for a lugnut to be able to warp a rotor

If they're over-torqued and any corrosion occurs on the threads, the breakaway torque necessary to crack the nut loose can exceed the shear strength of the lug...thus, broken lug nut.

The physics of how overtightened lug nuts can cause warped rotors was explained pages back. Over-torqued or unevenly torqued lug nuts can act as stress risers during thermal cycles (heating and cooling of the rotor). causing uneven expansion and contraction of the rotor, which leads to warping.

And most guns don't have 650 ft lbs of FORWARD torque. That's reverse torque.

The Snap-on MG725 is advertised as 810ft-lb in forward (1190 in reverse), and the IR 2135TiMax is listed as 550ft-lb forward. Both seem to be popular impacts.

 

[WhiffySpark]

I apologize for forward torque. Where did you find mg725 forward torque? I could have sworn it was something like 375 ft lbs

But I'm not buying your warped argument. We do hundreds of cars a month and I have yet to see it. But according to GJ there's so such thing as warped rotors so the point is mute. Lol

 

[JJThrasher]

I use sticks all the time at work, unless its a large truck or an old rusty pos with threads that are already dicked up. Both of which just get hammered down. I usually torque my wheels by hand or at least double check them. The main difference is that its my time and no one wants to pay me to hand torque.

 

[BrokewrenchLS1]

I apologize for forward torque. Where did you find mg725 forward torque? I could have sworn it was something like 375 ft lbs

But I'm not buying your warped argument. We do hundreds of cars a month and I have yet to see it. But according to GJ there's so such thing as warped rotors so the point is mute. Lol

Listed on the Snap-on site...although most manufacturers seem to have their own special adjectives to describe torque, making it a little hard to compare. IR doesn't even list forward torque (that I can find) for their 2235 lineup.

I've had it happen, and I know other people who have had warped rotors because of excess lug torque. The general **** quality of brake rotors today isn't helping things in the rotor longevity area, though, so it wouldn't surprise me if a lot of rotors warped due to excess lug nut torque get tossed as worn-out junk without an understanding of the root cause of the problem.

 

[Schurkey]

New 1/2"Torque wrenches at Amazon for $40-50.That will have to be the subject for a new thread.

All my torque wrenches are currently at the calibration shop. I'm paying fifty apiece to CALIBRATE them.

How accurate, repeatable, and durable do you suppose a $50 torque wrench is? The whole purpose of a torque wrench is to be accurate and repeatable and durable.

The torque sticks work much better with PVC air lines.

and that plastic coil hose at 1/4" diameter.

The local Discount Tire franchise uses a stick while the car is in the air and finishes with a torque wrench after the car is down. The franchise owner has made it clear that if anyone doesn't do it that way, they're fired.

Shop I bought my last tires at used the damned torque sticks. They tell every customer to come back within 50 miles to "re-check". They KNOW the torque stick isn't acceptable, but this policy puts the liability on the customer. Crooks.

My mechanic demonstrated how he could use his gun to torque my lug nuts to 80-90 foot pounds by feel. I was impressed. He said, "I've been doing this for 35 years."

I used to think I could do that...when I had a worn-out CP, or even when I moved-up to a Blue-Point 500.

I'm an amateur. I'll use a torque wrench.

Good plan.

Good article debunking Warped Rotors:

http://www.stoptech.com/technical-support/technical-white-papers/-warped-brake-disc-and-other-myths

Load of ****. The photo posted earlier showing the wear/warpage/thickness variation is worth a thousand of those articles.

When we moved up from a cheap impact wrench to a Snap-On IM510 27 years ago, the first wheel I put on I snapped the studs like nothing.

I went from a Blue-Point 500 to an IM510B that I bought used 'n' abused. Woof. Just f'n Woof.

That 510B would KICK *** on every one of the brand-new CP and IR impacts supplied by the Company. In fact, it was the only 1/2" drive impact in the plant that could securely tighten the 1 1/2" jam nuts that held the big copper Air Conditioning tubes. When that 510B was busy with me, my crew would have to hunt down a 3/4 drive impact to put the tubes in.

That 510B worked its *** off for ten+ years, then retired with me to occasional duty at home for another five or seven. There came a time that I thought it was getting feeble. I ran in a panic to the Snap-On man, and laid down money for an MG725. When I got home and went to transfer the whip hose to the new impact, I decided to remove the input fitting on the old gun...and found a screen behind the input fitting that was 1/3 covered in ****. I cleaned the **** out of the screen and the 725 sat in the bottom drawer of the tool box for three more years. I finally sold the 510B for what I'd paid for it twenty years before. Couldn't take the thought of the 725 feeling all lonely and neglected.

Actually, the torque stick should be more accurate than any torque wrench as it's based upon the hard and fast physical properties of a metal alloy. The only variable is the diameter of the torque stick and with modern CNC machines this is good to 0.0001 of an inch. If the spring steel from which the torque stick is made is right there is very little that can go wrong. A lot of things can and do go out of whack in a torque wrench.

A torque stick is a torsion bar. Repeat until it sinks in. Torsion bar.

You input enough torque (and I believe range-of-motion of each impact blow has an effect, also) and you'll get more torque at the fastener end, up to the yield limit of the torque stick.

Don't get me started on variation due to heating of the torque stick. You hammer on the input end with an impact wrench, where do you suppose the excess energy goes? It heats the material, and throws off the so-called calibration. Fortunately, smart folk don't rattle the 'stick until their ears bleed, and the 'stick doesn't heat excessively. We hope.

I remove lug nuts with a 3/8" Mac "High Torque" impact wrench that's as old or older than the 510B; and also purchased used by me. I hand-start each nut, then zip 'em on with that same Mac 3/8" impact. This gets me to about 40--50 ft/lbs. From there it's torque wrench to about 20 ft lbs under spec (if required), and then another round of torque wrench at spec.






Notes on torque wrenches: The ordinary 250 ft/lb or less "click-style" torque wrenches cost $50 to calibrate at the shop nearest me. An electronic torque wrench costs $125 to calibrate. Consider that before buying the electronic wrench.

I bought a Snap-On Torque Tester off of eBay. I paid very little for it, and now it's getting calibrated, too. That's costing just shy of $300 with a new battery pack--but now I can test and verify torque wrenches any time.

I got word earlier today that the little Snap-On 1/4" drive body with compact 3/8" head is no longer repairable. (Pawn-Shop purchase, I shoulda known better) Spring is weak, no parts available. All the others including the Jo-Line (dated 3-1974) are fine. Which brings us right back to "accurate, repeatable, and durable".

 

[2ndGearRubber]

Warped rotors or warped hubs while driving, seized lug nuts or snapped lugs the next time the tire comes off. No chance for damage, right?



Have you ever actually measured the torque applied at that gun setting?

I've had to replace a $250 set of rotors because a ******* blasted lugs on with an impact, so I tend to be a bit more careful with lug nut torque.

Yes. The torque wrench will spin the fastener a bit less than 1/4 of a turn, when set at 100. We've played with this debate a few times at work. No lug has ever been above 150, even when purposely being careless for the sake of letting the other side have its' argument.

It's not "gun and run". You run them in with a gun and tighten to a reasonable level of tightness.

But I'm not buying your warped argument. We do hundreds of cars a month and I have yet to see it. But according to GJ there's so such thing as warped rotors so the point is mute. Lol

By the logic of the over-tightening (or not torquing) causing warped rotors, I should be replacing a lot more rotors.

 

[theoldwizard1]

Watch them fasten the lug nuts at Costco !

The installer tightens them down using an impact and a torque stick. Then he double checks them with a torque wrench. Then A DIFFERENT SERVICE TECH checks them with a DIFFERENT TORQUE WRENCH.

Triple checked !

 

[Adam.C]

Watch them fasten the lug nuts at Costco !

The installer tightens them down using an impact and a torque stick. Then he double checks them with a torque wrench. Then A DIFFERENT SERVICE TECH checks them with a DIFFERENT TORQUE WRENCH.

Triple checked !

You can't "check" a fastener with a torque wrench. So these extra steps do nothing.

I agree with the fellow above. If you guys have questions, ask one of us who are engineers who deal with these sorts of things for a living. It isn't rocket science, but I think there's a lot of mythology floating around out there.

For you pros, if you were my sons I would tell you this is an opportunity for you to exhibit leadership. Do the right thing, don't cut corners, and find a way to set an example for your co-workers. If you want to be treated like a professional with specialized training and tools, act like one.

 

[Greg85mcss]

I have always been familiar with torque sticks but never saw them religiously used until I started my current job about a year ago. Before that everyone used the couple hammers then hand torque method & I agree that you get a feel for it. Now only one other guy hand torques. The sticks work pretty good but mistakes happen to the best of us. I stopped hand torquing for a couple days because everyone kept asking why I wasted my time if I was using a torque stick. Well I had an ******* that missed his appointment & was pissy that we wouldn't jump him in front of the people who were there on time. When I got his car in he was popping in from the waiting room to see how long every 5 minutes. I got frustrated & distracted & missed a wheel. We caught it before he left but I had to replace all the studs & it could have been much worse. I'll take one minute to double check my work.


Sent from my iPhone using Tapatalk

 

[Xicaque]

Interesting thread... I have been online for the past couple of days about torque sticks. I am a weekend mechanic and I do my wrenching for therapeutic purposes.

I think I will skip the torque sticks and do them with my torque wrench.

Never really understood how to tell when a torque stick is doing its job. I might have to peruse the YouTube library...

 

[abvw]

If they're over-torqued and any corrosion occurs on the threads, the breakaway torque necessary to crack the nut loose can exceed the shear strength of the lug...thus, broken lug nut.

The physics of how overtightened lug nuts can cause warped rotors was explained pages back. Over-torqued or unevenly torqued lug nuts can act as stress risers during thermal cycles (heating and cooling of the rotor). causing uneven expansion and contraction of the rotor, which leads to warping.
.

I fail to see how the clamp force on the top hat is going to affect the runout of the friction surface.

There is a lot of variation that can cause a pulsation in the pedal, the tightness of the lug nut has nothing to do with it, as I've torqued one side of the wheels with a $600 Snap-on torque wrench and my coworker blasted the lugs on the other side with an IR2135ti, no vibration even after 1 year. Did this on multiple vehicles during tire seasons never had any comebacks for brake pulsation that wasn't caused by a worn out, seized or defective part (seen quite a few brand new rotors out of round right out of the box).

It doesn't matter if the lugs are torque to spec or overtorqued, as long as they're torqued evenly, wheels don't fall off and it can be removed with the stock tire wrench, then its done right.

 

[Adam.C]

I fail to see how the clamp force on the top hat is going to affect the runout of the friction surface.

There is a lot of variation that can cause a pulsation in the pedal, the tightness of the lug nut has nothing to do with it, as I've torqued one side of the wheels with a $600 Snap-on torque wrench and my coworker blasted the lugs on the other side with an IR2135ti, no vibration even after 1 year. Did this on multiple vehicles during tire seasons never had any comebacks for brake pulsation that wasn't caused by a worn out, seized or defective part (seen quite a few brand new rotors out of round right out of the box).

It doesn't matter if the lugs are torque to spec or overtorqued, as long as they're torqued evenly, wheels don't fall off and it can be removed with the stock tire wrench, then its done right.

Wow. You guys just aren't listening. You are acting like children with your fingers in your ears, unwilling to hear something you don't want to hear.

Acceptable runout is .002". That's half the thickness if a sheet of paper. It doesn't take much to feel pedal vibration.

Over torque can cause a rotor to "festoon". Uneven torque, or even tightening using a ring pattern instead of a star pattern can also cause this VERY COMMON PROBLEM.

What I think you guys are struggling with is the idea of a puny bolt effecting that big lump of hard steel. Chances are, none of you have ever checked your brake job with a dial indicator. You need to think of steel as a spring. Each lug compresses it. It swells between them. If you torque the first fastener to full spec, you can warp it just like a head.

My guess is, none of you check your work and most average customers won't be sensitive enough to notice the vibration or care until wear increases to unacceptable limits.

I'm an aerospace engineer. Sounds like I have a few colleagues here. If you don't want to listen to us, Google the topic for yourselves. The advantage of boards like these is that we can learn from each other. I certainly don't know everything, but I know how brake rotors work. Don't want to believe me, Google it for yourself.

 

[jt777]

At the shop i work at its not flat rate and our boss says double click each wheel with the torque wrench

 

[saryon7]

Any idea how many foot pounds of force it takes to warp a rotor?


I've heard this for years, never seen it, or heard of it outside of theory. Wouldn't the hub surface require serious imperfections to force/load the rotor hat to flex that much? That, or wildly skewed torque between lugs? Maybe 500 ft/lbs on one lug, and the rest at 65?

I wanted to add a couple of things. I think the biggest reason rotors warp is not necessarily from over-torquing, but from cranking one lug all the way down to full torque and then crossing to the other lug and then torquing it down to full torque. This can make the first side actual torque value go way up. Even if the lugs are over-torqued a bit, but evenly torqued properly, I bet you wouldn't get a warped rotor.

And for those of you that say it is so bad to just hit it with the gun and walk away. My IR gun on level 2 puts lugs at just about a perfect 90 ft.lbs. every time. I had tested it many times with a torque wrench to just make sure. Crank the torque wrench to 90 ft. lbs. and I would get a click. Adjust to 95 and it would turn a bit, then click. I even had another tech question me about it. He didn't believe me, and tested it himself with the same results. So probably some of the techs aren't having problems because their guns are getting the lugs pretty close to the right torques, even though they are not using a torque wrench.

 

[SMKS]

You can't "check" a fastener with a torque wrench. So these extra steps do nothing.

They actually do accomplish something. They second person is checking to make sure none were missed and left loose.

 

[gsingh]

How would this cover you in the event a wheel fell off?

Torque wrench keeps records up to 50 times.