Changing tires - right torque?

[Shnak]

Alright, so I've finally decided to purchase an impact wrench and jack at CT to make my life a little easier when changing 8 tires twice a year...

Here's the impact wrench I bought (when on sale at 45$):
http://www.canadiantire.ca/AST/browse/6/Tools/2/CordedPowerTools/CordlessImpactDrivers/PRD~0542734P/Mastercraft%2B%25BD-in.%2B7.5A%2BImpact%2BWrench.jsp

Now, after reading on how to use it a bit, it says to only use it to remove the lug nuts, and to use a torque wrench at the recommended setting to install the nuts back.

Is there a real risk of screwing up the nuts/treads if I use the impact wrench to install the nuts again, letting it screw until the nuts stop turning?

If that really is a problem, then I can use a torque wrench I already have, very similar to one in following link, but it seems pretty flimsy to be applying any reasonable force.
http://www.canadiantire.ca/AST/browse/6/Tools/Wrenches/SpecialtyWrenches/PRD~0588660P/Torque%2BWrench%252C%2B1%252B2-in.%2B.jsp

So should I use the impact wrench to screw most of the nuts and then finish it off with the wrench? Is 80 lbs-ft good enough or should I look for the specific setting for each of my vehicles?

Thanks for the help!

[blur911]

The electric impact goes to 240lb.-ft of torque, far too much for putting on a wheel, only use it for removing the nuts or for running them in snug, but not tight.  Too tight and you can break a stud, warp a rotor or not be able to remove them again easily.
Your torque wrench is  perfect for tightening them up the last bit, while it is probably somewhere around 80lb.-ft for your lug nuts check to see what is the actual spec.

[Shnak]

Ok thanks, that's what I thought (after reading a bit!).

Unfortunately, I changed all 8 tires with only the impact wrench this weekend. I stopped 'torquing' as soon as the nuts wouldn't turn anymore... hopefully I haven't done any damange!! And of course, I forgot to take into account for the rotational direction of the tires before putting them on, and now, I have to switch 6 of them... you'd think that I would have remembered this after making the same mistake on the Sportage's tires last winter!!! 

Again, thanks for the input.

[articsteve]

If your torque wrench is any good then 100 lbs. on steel wheels is pretty well the standard.

[Shnak]

I couldn't find an exact spec for my Accent, but the Sportage's owner's manual says 67-75 lbs/ft... does that apply only to the allow rims, and not steel wheels?

[articsteve]

Put it this way, if you took your steel winter wheels to the Hyundai dealer the service guy would use a 100lb. torque stick guaranteed.  Dealers to not install those steel wheels with less torque.

If you wanna put only 75 lbs then go ahead.  Are you absolutely sure that when your torque wrench says 75 lbs. there is in fact 75 lbs. on that stud     Thats the thing, nobody wants these wheels coming off so it's usually a standard 100 lbs. which causes no ill effects to the rotor or what have you.

Wheels comes off, spouse or son/daughter paralyzed ... was the dinking around over 20 lbs/ft worth it. 

Go with 90 lbs. if your torque wrench is a known quanity.  If not set it to 100 lbs because most likely is 10 lbs. short.
 

[safristi]

Just a SHOUT OUT TO ALL THE BRAIN DEAD MECHANICS don't fackin' torque wheel NUTS to INFINITY...............

[Rupert]

A lb. is only a weight or force measure. If refering to torque it has to be accompanied with a radial distance...ft, ins, meters...whatever. ie., Lb.ft. otherwise it is meaningless. If someone took Lb. to mean Lb.ins. a disaster might occur and you might be the driver getting a good look at the wheel that just leaped the central barrier.

[articsteve]

If refering to torque it has to be accompanied with a radial distance

Only in your world Rupert. 

[mrthompson]

 

[airbalancer]

Put it this way, if you took your steel winter wheels to the Hyundai dealer the service guy would use a 100lb. torque stick guaranteed.  Dealers to not install those steel wheels with less torque.

If you wanna put only 75 lbs then go ahead.  Are you absolutely sure that when your torque wrench says 75 lbs. there is in fact 75 lbs. on that stud     Thats the thing, nobody wants these wheels coming off so it's usually a standard 100 lbs. which causes no ill effects to the rotor or what have you.

Wheels comes off, spouse or son/daughter paralyzed ... was the dinking around over 20 lbs/ft worth it. 

Go with 90 lbs. if your torque wrench is a known quanity.  If not set it to 100 lbs because most likely is 10 lbs. short.
 

You really think they would use a torque wrench, I think he would use an impact gun

[toolatecrew]

Using an impact gun with max 240lb ft to put them on is asking for trouble.

I ended up getting a battery powered one a couple years ago thinking it said maximum XXX lb lbs when in fact it says xxx inch lbs. So it actually has a max torque of less than 80 ft lbs. So I use the cordfed 240 fl lb one to take them OFF. The battery powered 80 ft lb one to put them ON and then tighten with a toque wrench.

Some places do use an impact gun but wiht a torque limiting attachment to keep from overtightening. Regardless you should still scheck with a torque rench. The owners manual should give a range for the lug torque. Go towards the upper end if you are concerned about the wrench being innacurate.

[rrocket]

If it's a decent impact wrench, it will have 5 settings so you can snug things up less than 240lb/ft.  Some of the good ones have 12 settings.  But you should always use a torque wrench to get nuts to the proper torque setting.

[blur911]

If it's a decent impact wrench, it will have 5 settings so you can snug things up less than 240lb/ft.  Some of the good ones have 12 settings.  But you should always use a torque wrench to get nuts to the proper torque setting.

That's the problem with the A/C electric ones, there is only on or off, no adjustments.  I have pretty much the same one as Schnak and it can easily overtighten nuts.   
I also have a pneumatic one with adjustments and yes, you can turn it on low to run them in and finish off with either a torque wrench or a fit a torque stick to it and turn up the power.

BTW Schnak, remember to float the pivot on the handle of your torque wrench to get an accurate reading.

[Zombie]

I have that corded impact wrench from CT, it's a beast. Don't use to to tighten the nuts only use it to thread them on if you must but I usually just use my digits for that part. I currently use a torque wrench (the good one from CT) to put the nuts on but I used to just use the lug wrench in the trunk that came with the car. If you don't have or don't want to get a torque wrench this will be good enough as long as you have some man hands.

[dr_spock]

I believe you can use a torque stick on your impact wrench to tighten your nuts to specs.   Overtighten can also warp your brake rotors.   It is best to use the car manufacturer's specs. 

[HeliDriver]

I've always wanted to get one of these. Seems like a quick way to spin the nuts off and on, then just finish up with the torque wrench.

[Minou]

Bought one in the US last year for only $10.  Very handy.  Places like K-Mart or Walmart carry them.  Here, it's about double that price.

[mrthompson]

I've always wanted to get one of these. Seems like a quick way to spin the nuts off and on, then just finish up with the torque wrench.

I use one of those and measure the torque by the number of grunts whilst tightening the lug nuts. 

[safristi]

despite having one of 'em "star"cross NUT PULLERS (ouch)........couldn't get one wheel off
 to put on my son's winters....stood on the lug wrench and NOT a peep of a movement!!!! ...........he'd just had some work done @ a VW dealership in London (Leavens VW..winners of  VW service award for Ontario!!!) and the wheel that was OVERTIGHTENED was the one they removed for service.............wdf!!!.............to me (and i did complains..."we will pass that along " response garners nothing i'm sure) to me the correct torquing of TYRES should be a NO FAIL ISSUE.................imagine being stuck in the boondocks in Winter with a flat ...and ya can't remove a wheel to put on the spare.BLOODY STUPID.....next time I'm gonna make a BIG FUSS.....and see the torque is right and the tyre removable by a 100 lb weakling (any takers on here?  ).to me this is a BIG DEAL wot say U 1010 Tyre Guy........?