Lug Nut Torque

[exdotcomer]

bought a new impact gun and would like to rotate my tires. I need to hand torque the lugs after i put the rims on, any idea as to how much?

[mburnickas]

Here is my values for a Es300 (from my mellon). They should be around 76 ft-lbs +/- 3 ft-lbs. Or 103 N-m (joules) +/- 4 (joules)

[exdotcomer]

kewl, thanks!

[mburnickas]

Also make sure you put some lube on the threads. It will increase the torque by a small percent (3 to 8) but it will not harm the threads (cross threading etc).

Lastly, try to install in the cross pattern. If there are 5 lugs: tighten lug at 2 (o'clock position) to 7, then to 12, then to 4 then to 10.

If not, do not worry that much.

[99lsguy]

Also make sure you put some lube on the threads. It will increase the torque by a small percent (3 to 8) but it will not harm the threads (cross threading etc).

Lastly, try to install in the cross pattern. If there are 5 lugs: tighten lug at 2 (o'clock position) to 7, then to 12, then to 4 then to 10.

If not, do not worry that much.

Agree with completely

Also, I set torque to 65 ft. lbs for FIRST STAR PATTERN, then I up it to 76 ft. lbs. and star pattern again :D

[exdotcomer]

wow- you guys know your stuff! Thank you very much!

[exdotcomer]

Also make sure you put some lube on the threads.

uumm, any more detail on the lube?

[mburnickas]

Some lubes have a certain values it increases. I have a list at work, from Mark’s Standard Handbook for Engineers (Bible in engineering world), named many lubes with their respective base material. Like some are moly based, silicone, alum-oxide, etc.

To sum it up, each lube lowers the coefficient of friction. So by lowering the friction it will increase the torque for that thread. As long as you do not yield the bolt/stud you are fine. Do not worry it will take a lot to cross-thread the bolt. You can figure it (cross-threading) out with some basic formula but no need to.

The only formula I remember is: T=(K)(F)(D)

T=torque (ft-lb, N-m whatever units you have)

K=torque coefficient or nut factor (Lube chart)

F=Nut load or clamp force

D=nominal DIA of bolt (in, ft, m)

I use anti-sneeze J (seize) on my lugs; however, you can use engine oil, chain lube etc. Anything is better then nothing. Just try to remember the torque formula in case you torque to max, which is perfectly fine, and add a certain lube. It will case the torque to go over you max. Just be aware.

[SmoothOperator]

I sure hope nobody followed this advice for adding lube to the studs. What can require 55 ft-lb torque dry, only needs 30 ft-lb lubed. This is at least 80% over torqued condition. You can seriously over stress the threads and the studs and/or nuts will fail! The torqued values given are from the manufacturer are for dry conditions. Do not modify this for your own safety. Two degrees in Mechanical Engineering and a career in machine designing gives me the qualifications for these statements.

[99yoToya96]

Okay. I know this is an old thread but I feel I need to add some clarification. I’m an old hand with wheels/tires/fasteners, and asked this same question at every manufacturer & tire safety training I’ve attended in the last 30 years. So here goes:

Lug nut torque values assume clean, DRY threads. There is absolutely NO reason to apply any type of lubricant, anti seize, etc to wheel stud threads. If they are rusty, clean them with a wire brush. If you can’t spin the lug nut on by hand, the threads on either the stud or inside the nut are not clean enough. The only place that oil is permitted by “most” wheel manufacturers to be applied, usually in the form of a single drop of 30w machine oil, is between a nut and its captive washer to facilitate a proper torque reading upon final tightening. NEVER between the washer and the wheel, a tapered nut and the wheel, or on the actual threads of the stud or nut. 

This is well-known to anyone that has received training on heavy truck tire mounting & installation, but it applies just as well to light automotive. The shop manuals I happen to have in front of me today are for a 1996 Dodge Ram and a 1999 Toyota Camry. In the “Wheel & Tire” section of both manuals, as well as just about any other shop manual you check, it makes this statement in bold type: “Never use oil or grease on studs or nuts.” It states that if surface rust, oil, or grease is present on the studs or nuts, they must be fully cleaned and degreased prior to assembly.

As an aside: anti seize on wheel studs really doesn’t serve any purpose...if you’re leaving lug nuts in place long enough to seize to the studs, you’re not properly maintaining the vehicle in question. An extremely thin coating of anti seize can be applied to the hub on hub-centered wheels, or the wheel surface that contacts the rotor, to help prevent corrosion & seizing, but never on the wheel studs themselves. 

I sincerely hope this helps someone. 
 

[Bykfixer]

Very good info 99yoToya96. Thank you!! Welcome to the site. 

I learned as a bridge inspector that a given torque applied assures proper tension (as in amout of pressure applied between two items) so adding lube can reduce the resistance as the bolt tightens, which can result in an increase in that tension beyond what one or both items was designed for. 

Too much clamping force can weaken a wheel or stretch the stud. One other thing many may not consider is warping a brake rotor when over tightening occurs. So applying lubricant can also contribute to that. 

On bridge bolts and traffic signal mast arms wax is applied as a rust inhibitor but that is factored into the pressures applied and confirming the numbers using sample bolts. 

We use dial type (not to be confused with beam type) torque wrenches as using a clicker can be slightly inacurate and often times folks like to confirm click 1 with a click 2. That is also a no no. Click once and stop. Also don't forget to have your torque wrench calibrated.