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I used to think that it was necessary to use a torque wrench to tighten the nuts securing the tire/rim to make sure they are tight enough without stripping the bolts. But this video https://www.youtube.com/watch?v=iJAI-cy2fZc doesn't even mention a torque wrench. I'd like to change the tires on my car myself if it's safe to do so with only the equipment that comes with the car.

  • Welcome to Motor Vehicle Maintenance & Repair! – Pᴀᴜʟsᴛᴇʀ2 Dec 14 '17 at 16:52
  • Do you have steel wheels and steel lugnuts? Or alloy wheels and/or alloy lug nuts? – mikegreen Dec 14 '17 at 17:32
  • I don't know if they are steel or alloy. I ended up getting a cheap torque wrench, and the owner's manual gives the range of torque to tighten to. – Alan Dec 14 '17 at 19:50
  • @Alan you’ve stumbled on one of our default answers: always do what the owners manual says! – Bob Cross Dec 15 '17 at 12:40
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While a torque wrench is not absolutely required, it's a good idea. You need to ensure the wheel is evenly clamped onto the hub. This prevents the wheel from warping and causing other issues. Using the lug wrench which comes with the car will get you down the road.

As a rule of thumb, I torque steel wheels to 80 lb-ft (50 lb-ft first pass; 80 on second pass, with a double check), while alloy rims will get 100 lb-ft (70 lb-ft first pass; 100 on second pass, with a double check).

You can get a decent torque wrench for cheap from the likes of Harbor Freight here in the States (not knowing where you're from). I've seen their 1/2" drive ratchet/click type ones go for as cheap as $11 on sale. Well worth the minor investment.

  • Thanks for the answer. I didn't realize they were that cheap, I'll probably pick one up. – Alan Dec 14 '17 at 17:19
  • If you want to know what torque to torque the wheel lugs to, check your owner's manual. Wheel lug torque is the one torque measurement that's usually mentioned in the vehicle's owner's manual. – Ives Dec 14 '17 at 18:33
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    The ratchet/click type ones should ideally be calibrated occasionally, and guess what is the calibration method? It is a beam-type calibration standard. So, I would pick a beam-type torque wrench instead because they require no calibration. They are usually cheaper, as well. Not as handy in tight places, but for wheel changes okay. – juhist Dec 14 '17 at 20:30
  • absolutely if you want to go cheap and only need occasional use get a beam-type wrench. $25-30 for a decent one. I don't think i'd trust a clicker that was that cheap. – agentp Dec 14 '17 at 22:29
  • @agentp - Read the caption underneath this photo from Hot Rod Magazine in reference to the Harbor Freight 1/2" drive torque wrench (this is from 2013). HF states the torque wrench is +/-4% and HRM's testing shows its right in there. Yah, a Snap On one will get you closer, but at what cost? – Pᴀᴜʟsᴛᴇʀ2 Dec 14 '17 at 22:38
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A torque wrench is not explicitly necessary; the spare jack and tire iron that come in the trunk of every car are sufficient to change a tire in normal cases.

If this was the case, car manufacturers would have to start including torque wrenches with the car in the event of a flat tire.

  • In the 80s, I would tend to agree. Now, they are barely enough to use in an emergency, and they are often a pain to get out of the car. – Doug Dec 15 '17 at 22:21
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What the other answers failed to realize actually is that the wrench that comes with a car actually IS a torque wrench!

The length of the wrench is carefully chosen so that most people with average strength naturally torque the lug nuts with the provided wrench approximately to the correct torque.

Yes, it is a very inaccurate torque wrench but still it is a torque wrench. The reason why this is enough is that there is huge safety margin in the torques of lug nuts. 30% too low torque? No problem! 50% too high torque? Not a problem either! In one of the cars I owned, I accidentally looked at the wrong scale on the torque wrench and torqued to 120 lb ft (remembered incorrectly the torque would be 120 Nm), while the correct torque was 110 Nm. The torque 120 lb ft was 163 Nm, 48% too high. No damage done.

Edit: and a factor in the correct torque is also that most people have some amount of muscle memory. They have the tendency to remember how hard they had to untighten the lug nuts, and thus remember approximately the correct force when tightening again.

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    A torque wrench with a +/-50% variance? That sounds like a great option. Not sure how you can consider a lug wrench a torque wrench, when the whole idea of a torque wrench is some semblance of accuracy. Each to his own, I guess. – Pᴀᴜʟsᴛᴇʀ2 Dec 14 '17 at 22:03
  • Average strength is very subjective. The wrench that comes with your car is for emergencies. – Doug Dec 15 '17 at 22:17

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