Lug Nut Torque

[NASTNSX]

Does anyone know what the torque setting should be for the front & rear lug nuts?
Thank you in advance for any 411.

 

[DanO]

80 lb-ft

 

[RP-Motorsports]

I usually do about 90. Maybe because I have had them come loose on the track at anything less than 90.

 

[Briank]

I usually do about 90. Maybe because I have had them come loose on the track at anything less than 90.

That's interesting, 80 Ft LB should be more then adequate. Is your torque wrench working properly? Also a little lubrication on the threads helps get a better torque.

 

[RP-Motorsports]

Works fine, and I know a lot of people who use 90 as well

Brian are you going to RA anytime soon? I would like to meet you. A few NSXers will be there April 18th watching the fools crash during the armco-seekers oh I mean speedseekers event. We will also be there for Windy City as well.

 

[KGP]

90 lb. ft.

That is interesting. I have had a wheel come loose after wrenching to 80#, but it wasn't on the track. So, what might be the possible ill effects of over-torqueing other than making the lugs hard to remove? How much is too much?

 

[Yellow Rose]

I use 80 and have never experienced anything loose - street or track.

Be careful with lubricant on critical threads. Required torque values are calculated to arrive at a certain stress level in the threads. Lubricant reduces the coefficient of friction in the mating surfaces of the threads. Lower friction can lead to artificially increasing the stress in the threads at the same torque value. The purpose of torque is to actually stretch the male fastener so that it "pulls" the nut onto the wheel, holding it firmly to the hub. Lubricant = more torque = overtightened stud = broken stud = profanity. In thirty years of playing with cars, I have never lubricated a wheel stud and have never broken one nor found a nut to be loose that was properly torqued.

 

[Briank]

90 lb. ft.

That is interesting. I have had a wheel come loose after wrenching to 80#, but it wasn't on the track. So, what might be the possible ill effects of over-torqueing other than making the lugs hard to remove? How much is too much?

It surprising how much torque the lugs will take, most repair shops just run them tight with a air wrench making them so tight they can be hard to remove.

 

[Taj]

That is interesting. I have had a wheel come loose after wrenching to 80#, but it wasn't on the track. So, what might be the possible ill effects of over-torqueing other than making the lugs hard to remove? How much is too much? [/B]

I usually torque the nuts twice. I would torque the nuts, take it out for a spin and re-torque them again. Once in a while, couple of the lug nuts relax and drop below the specified torque value. As Andy mentions, do not lubricate the fasteners unless it is specified in the manual. Lubricant increases the pre-load/tension of the fastener with the same torque value. As a result of using lubricant, the fastener could be permanently stretched (yield) and eventually broken off.

Well, how much is too much? I don't have a specific number for you since torque does not translate into tension very well. The torque value is dictated by a desired tension. It is usually obtained by actual measurement. As long as the lug nuts are not over torque to the point of permanently stretched, there is no ill effect to the studs and its material properties.

 

[DanO]

Service Manual page 18-15: Lug Nut Torque = 80 lb-ft. If your lug nuts are coming off at this setting then something is off. Either the Service Manual setting is incorrect, the torque wrench is off or there is some other kind of modification going on that are causing the loose condition.

I've never had a problem with 80 lb-ft on or off the track.

BTW, my other 5-stud cars manual's say 90 lb-ft. Go figure.

DanO

 

[NSXSOON]

Torque wrenches are not all designed equally. Most are the spring tension type (turn the handle to set and cost less than $100 in most cases). The trouble with these, and what most people are unaware of, is that if they are not returned to zero setting/setting when they are put back in the tool box there calibration is gone. Even forgetting one time can throw these off in a non linier fashion. Most of the better ones (dial type) don’t suffer from this short coming. A good Snap On torque wrench can set you back $200+ but is very accurate and holds its calibration well. They can also be checked and re-calibrated every two to three years while the spring tension type can’t be calibrated at all.

 

[RP-Motorsports]

Most studs can handle over 100 ft lbs, but it is the lugs that are the weak link. Anything over 90 ft lbs on Gorilla spline nuts, will cause them to stretch, and will then cross thread the studs on their way back off! (ask me how I know this ) Even the weakest lugs can handle 90, but never go over 90 EVER! 80 to me is too weak, 90 seems just right. I do all my cars @ 90 and no problems. Also stay away from Gorilla splines!!! Get something of better quality.

 

[KGP]

Thanks Dano and T Bell. If I have the luxury, and am going to err, it's going to be on the side of safety.

 

[juejaimon]

Torque wrenches are not all designed equally. Most are the spring tension type (turn the handle to set and cost less than $100 in most cases). The trouble with these, and what most people are unaware of, is that if they are not returned to zero setting/setting when they are put back in the tool box there calibration is gone. Even forgetting one time can throw these off in a non linier fashion. Most of the better ones (dial type) don’t suffer from this short coming. A good Snap On torque wrench can set you back $200+ but is very accurate and holds its calibration well. They can also be checked and re-calibrated every two to three years while the spring tension type can’t be calibrated at all.

ARGH!.. i've always left my torque wrench @ 85... I have the "turn the handle" one. Seems like I need to get a new one now..

Thanks for the informative thread!

 

[nsxtasy]

I have an inexpensive "turn the handle" kind of torque wrench, and have not bothered resetting it to zero. Ever.

I had it calibrated after several years of such use and it was still dead accurate.

Just another data point...

 

[RP-Motorsports]

Ken, what do you torque yours at? Do you do the same for the ITR as the NSX? I have seen everything between 80-100, but I feel 90 should be a max. What cracks me up is seeing people at the track with the OEM bar, and cranking it and actually kicking it tighter with their foot!

 

[nsxexotic]

For safety I would tighten the lug nuts as much as I could with the tire in the air. Release the jack just enough so the tire grips the driveway... torque all lugs. Bang on the tire a couple times. Raise the car up again and spin the tire half way around. Lower the car and check torque again.

 

[apapada]

Most studs can handle over 100 ft lbs, but it is the lugs that are the weak link. Anything over 90 ft lbs on Gorilla spline nuts, will cause them to stretch, and will then cross thread the studs on their way back off! (ask me how I know this )

At my first track event with the NSX the tech inspection guys overtorqued my lugs at 90 without me realizing it. It cost me a set of warped AutoSpecialty high-performance cross-drilled rotors. The lugs are NOT the weak link. Many Hondas will have their rotors warped if lugs are overtorqued, the NSX seems to be no exception.

Even the weakest lugs can handle 90, but never go over 90 EVER! 80 to me is too weak, 90 seems just right.

It does not matter what seems right to me or to you. 80 is the nominal value that was engineered for this car.

I do all my cars @ 90 and no problems. Also stay away from Gorilla splines!!! Get something of better quality.

Why would something designed for one car should work best for another car? In the same logic, everyone should use the same motor oil and try to upshift at 7,500 RPM with any other car other than the NSX as well.

At the second event I went, I politely asked the tech inspection guys not to overtorque the lugs. They still did although saying they wouldn't. I retorqued them to the 80 lb-ft setting and checked them after each session. They never came loose and no rotors warping this time (stock rotors this time)

 

[ncdogdoc]

I have (incorrectly) been running 72 lbs for almost a year now, both on the track car and the street car, no problems. Why, you ask, would I do something this stupid? Well, my 2 1/2 ton Lexus LS400 only uses 72 lbs, and since I am switching snow tires/wheels about as much as I change setups on the track car, I ended up using to lower setting. Oh well.

 

[nsxtasy]

Ken, what do you torque yours at? Do you do the same for the ITR as the NSX?

80 ft-lb for both cars, same as specified in the service manual for both cars.

What cracks me up is seeing people at the track with the OEM bar, and cranking it and actually kicking it tighter with their foot!

Some folks here may not know how to use a torque wrench, so everyone else please bear with me for describing how it works. When you tighten a nut or fastener with a torque wrench, it makes a click as soon as you reach the specified force. DON'T TIGHTEN IT BEYOND THAT POINT! It is possible to keep tightening it, but if you do, you will be applying more force than you set it for - which undermines the whole reason for using the torque wrench.

 

[RP-Motorsports]

At my first track event with the NSX the tech inspection guys overtorqued my lugs at 90 without me realizing it. It cost me a set of warped AutoSpecialty high-performance cross-drilled rotors. The lugs are NOT the weak link. Many Hondas will have their rotors warped if lugs are overtorqued, the NSX seems to be no exception.

90 ft lbs on a Honda equally on each stud, will NOT warp your rotors. Since it was your first event, you probably left your brakes on after the first session!

Heck the Z06 guys run anywhere from 90-110 at the track. Some upgrade to ARP studs, and step torque to 115.

I never told people to use 90, I just stated that is what I use, and many people at the track that I see do as well. Heck I have seen a few NSX owners set it at 100 at the track.

I say 80 is fine, as long as you don't go under that for the track. I have witnessed many people with missing or loose lugs that have followed mfg specs on many different marques at the track.

The more important thing is what Ken stated DO NOT turn anymore after the "click" also do NOT tighten them clockwise or counter, go opposite of the previous lug on a zig zag pattern. Some believe in step-torqing as well, where you torque them all to 30, then all to say 60, then all to say 80. Others say that is a waste of time. And lastly check them after each session.

 

[NSX 3.0]

I torque mine down to 90 ft lbs also and have never had a problem what so ever.

 

[nsxtasy]

Since it was your first event, you probably left your E-brake on after the first session!

Doubtful.

Oh, I know that you can warp your rotors by using the parking brake after a hot track session - but that would only warp your REAR rotors. That's pretty rare; most people develop problems with their FRONT rotors. And all too often, the rotors aren't actually warped, but they have deposits of brake pad on them, which is exacerbated by improper bedding. Read this for more info.

 

[apapada]

90 ft lbs on a Honda equally on each stud, will NOT warp your rotors.

Are you calling me a liar ?

Since it was your first event, you probably left your E-brake on after the first session!

If you had taken the time to read my post correctly, you would have noticed that I stated it was my first event WITH the NSX, not my first event ever. You seem to be jumping to conclusions a bit easily...

Also, FWIW the warped rotors were the front ones, kinda difficult to warp them with a E-brake, no ? whaddayathink?

Heck the Z06 guys run anywhere from 90-110 at the track. Some upgrade to ARP studs, and step torque to 115.

So, if I follow you correctly, this should extend to the NSX as well... or NOT, and you might just be jumping to more conclusions too easily...

Just think about the argument you are making ? How does it relate against the FACT that the NSX manual clearly states 80 ?

 

[apapada]

Doubtful.

Oh, I know that you can warp your rotors by using the parking brake after a hot track session - but that would only warp your REAR rotors. That's pretty rare; most people develop problems with their FRONT rotors. And all too often, the rotors aren't actually warped, but they have deposits of brake pad on them, which is exacerbated by improper bedding. Read this for more info.

You are right Ken. It's the front ones that warped. I was aware of this article (you've posted it b4 I think) and checked the rotors myself. They are clean and free of any pad material. Checking them with a micrometer gauge however it was confirmed to me that they are warped. Not much, but enough to cause a bit of vibrations under heavy braking. I'll try to have them turned and see.