Why Rotors Warp
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From: Farmington, Minnesota =MWBF '05 SURVIVOR= =CEBF '06 SURVIVOR= =August '06 COTM=
I've never warped rotors from not using a tq wrench..I snug them down until they're firm, then I'll wrap'em down with the impact on about a medium to a 3/4 power setting.
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From: Texarkana, Texas
Walmart uses sticks and a wrench, On most cars the stick gets with within 10 pounds or so when you click it. As long as they're not just ramming that thing or letting it sit and hammer I'm fine with them.
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Using a torque wrech to go back and test how tight your lugs are is pretty pointless. In fact, your time with the torque wrench in hand would be better spent starting over and torqueing them yourself.
In cases where people are suffering from prematurely warped rotors, where inferior parts can be out ruled, I would say 90% of the time over tightening is the cause. Wether the installler realizes it or not.
I used to have an old tool catalog full or useful info such as: the average inexpensive torque wrench, when used infrequently, can become read as much as 30-40% off from actual within a year'* time- and they often arent worth having calibrated. If you want a torque wrench to rely on, spend the $ for a quality professional grade one. Also, using a deep well socket when not needed, and using even a short extention throws off the readings. If you are only using your unit for checking lug nuts, have it calibrated with the extention installed.
[quote="jr's3800"]
Actually this is the procedure at chain stores due to the fact that the minimum-wage idiots working there are very prone to forgetting to reinstall all the lug nuts. The theory is that these ****-ups are eliminated by double checking.
Torque sticks are an interesting invention, and are becoming the industry standard. Its really up to the user to judge wether or not they really are accurate.
An expierenced mechanic is able to properly install lugs WITHOUT overtightening without anything more than their regular impact gun. They do it "by feel" if you will.
In cases where people are suffering from prematurely warped rotors, where inferior parts can be out ruled, I would say 90% of the time over tightening is the cause. Wether the installler realizes it or not.
I used to have an old tool catalog full or useful info such as: the average inexpensive torque wrench, when used infrequently, can become read as much as 30-40% off from actual within a year'* time- and they often arent worth having calibrated. If you want a torque wrench to rely on, spend the $ for a quality professional grade one. Also, using a deep well socket when not needed, and using even a short extention throws off the readings. If you are only using your unit for checking lug nuts, have it calibrated with the extention installed.
[quote="jr's3800"]
Originally Posted by BillBoost37
I watched sears do it once, I firsy saw them use an impact, then they lowered the car onto the ground and torqued all of the lugs to spec with a torque wrench 
Torque sticks are an interesting invention, and are becoming the industry standard. Its really up to the user to judge wether or not they really are accurate.
An expierenced mechanic is able to properly install lugs WITHOUT overtightening without anything more than their regular impact gun. They do it "by feel" if you will.
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From: Ames, Iowa
Originally Posted by optmusprimer
Using a torque wrech to go back and test how tight your lugs are is pretty pointless. In fact, your time with the torque wrench in hand would be better spent starting over and torqueing them yourself.
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From: Berkeley, IL
Re: Why Rotors Warp
Originally Posted by bill buttermore
Took the SSEi to a local garage to have the tires balanced this morning. On a hunch, I took my torque wrench, a short extension, and a 3/4" deep socket along. When they were done, before I drove away, I torqued all the lug nuts to 100 ft-lbs. They had used an impact wrench to tighten the nuts. On the left front front wheel, here are the torque settings I found as I tightened the nuts in a star pattern:
..................................40
.......................80..................70
.............................50.......60
With this kind of uneven tightening, is it any wonder that rotors warp? Of course, they do brakes, too. I'll bet they change a lot of rotors.
..................................40
.......................80..................70
.............................50.......60
With this kind of uneven tightening, is it any wonder that rotors warp? Of course, they do brakes, too. I'll bet they change a lot of rotors.
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From: Enfield, CT
Originally Posted by optmusprimer
Originally Posted by jr's3800
Originally Posted by BillBoost37
I watched sears do it once, I firsy saw them use an impact, then they lowered the car onto the ground and torqued all of the lugs to spec with a torque wrench
And if you think a mechanic can get them to the correct torque by feel you are mislead. I know many mechanics. They can get reasonable with an impact, there are too many factors though. Air pressure for example. A good mechanic will torque stick or torque wrench.
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And if you think a mechanic can get them to the correct torque by feel you are mislead. I know many mechanics. They can get reasonable with an impact, there are too many factors though. Air pressure for example. A good mechanic will torque stick or torque wrench.
An expierenced mechanic is able to properly install lugs WITHOUT overtightening without anything more than their regular impact gun.
<shrug> hey its not like I spent years working as a mechanic, or learned tricks of the trade from 30+ year veterans right?