I generally put a touch of anti-seize on wheel studs before tightening down lug nut - would like to hear others' opinions on this practice or what else they may use...
With Big trucks if DOT inspectors see anti sieze on lug nuts the truck is parked. I have no idea if it is good or bad.
Absolutely not. The lubrication will allow the bolts to over tighten and stretch, the torque specs and clamping load are set for clean dry threads unless specifically stated otherwise. I have heard of wheel studs failing before reaching torque spec. Put a stud in a vice and using washers torque it to spec, measure the bolt. Then coat it with anti-seize and try that again...
I use anti-seize as well and I've never had a wheel fly off. I also use a torque wrench to install them and not a 4 way.
I usually dab lube on them very lightly and then wipe them off. However, one my 1 ton, I put the nuts on bone dry. My dad greased all his lug nuts and never lost any nuts, ever.
I've always used a little oil or antiseize, and never had a wheel get loose. I have had dry wheel studs that almost wouldn't come off! I just pulled the wheels on my '63 Falcon project, and they were dry. They came off hard all the way, and will never accept a nut again without a thread chaser first.
I don't use a "touch", I use a lot including on the lug nut tapers. I also back off a little on the perceived torque being applied since the reduction in friction increases clamping force for a given torque. Bob
From crashforensics dot com Crash Forensics provides wheel and hub failure analysis services for passenger vehicles and heavy trucks. Failure analysis services can be conducted "on site" from our mobile lab or "in house" in our automotive lab. Below is a discussion of wheel and hub failures. Link to our automotive expert. Crashes caused by wheels coming off of vehicles are commonly referred to as wheel runoff crashes. Two primary failures cause wheel runoff crashes. One is a failure of the wheel mounting system, such as the wheel studs, lug nuts, etc. The other cause is a failure of the hub and wheel bearing assembly. Most commonly, these failures are related to improper or deferred maintenance, but some are also linked to manufacturer's defects. Wheel System Failures Wheel system failures are primarily caused by the improper installation of a wheel that causes it to be loose or become loose. Commonly, a loose wheel causes the wheels studs to break and the wheel and tire to separate from the vehicle. Many root causes lead to loose wheels, but most of them are associated with over-torquing or under-torquing the lug nuts. A bolted joint, such as a wheel mounting system, works by tightly clamping two surfaces together. The friction of the two mated surfaces and the force created from clamping them together with bolts (Clamp Load) allows the surfaces to resist movement. The amount of friction and Clamp Load determines the level of resistance the joint has to movement. Clamp Load is created by tightening the bolts against the mated surfaces and is normally measured in foot pounds of torque with a torque wrench. If the bolt torque specified for a joint is applied, then the resultant Clamp Load should also be within specification. However, variations in the system such as rust or lubrication on the threads can affect the Clamp Load vs. torque relationship. Items in place between the mated surfaces can reduce the joint's friction and also alter the relationship between bolt torque and Clamp Load. This is called a Soft Joint. Two concepts are important to understanding how a bolt works. They are Elastic Deformation and Yield Point. Elastic Deformation is metal's or, in this case, a bolt's ability to stretch and spring back to its original shape. Yield Point is where the bolt has been stretched past its elastic limit and can no longer spring back to its original shape. This stretching of a bolt and its pulling back creates Clamp Load. If, however, a bolt is over-torqued, and stretches past its Yield Point it can no longer maintain the Clamp Load. Over-torquing is likely the most common wheel system failure due to the widespread use of impact wrenches to install wheels. Using an impact wrench to install wheels commonly causes the wheels to have 3 to 5 times the specified lug nut torque. The use of lubricants and anti-siezing compounds on the threads of the wheels studs or lug nuts can cause an even higher degree of over-torquing.
This really is a very interesting question, one for which I have never had a good answer. I generally antiseize the crap out of every fastener I use, especially stainless fasteners, but I have never known what to do on wheel studs. I have used a dab in the past but not always, and have wondered which way is correct.........to use it or not. I have never seen any car come off the assembly line with any on the wheel studs, but not sure if that means anything or not. Very confusing. Don
We lost wheels...As teenagers, we took a 69 roadrunner well past 100 mph, twice. The next day the front wheel fell off. All the studs broke. The tow truck lifted it up and the other front wheel fell off. Moral of the story...Never run a ford wheel on a mopar...at least not without checking to make sure the center hole is the right size. oh, we probably greased the lugs on it too.
The lubrication will allow the bolts to over tighten and stretch, the torque specs and clamping load are set for clean dry threads unless specifically stated otherwise.
you can run mopar wheels on a ford but the wheel ecentric hole is too small for a ford wheel to seat propperly on a mopar
In this cold north, I have always used a light wipe of anti sieze, and used the lower end of the torque value. I have seen two value sets recommended, for dry and lubed threads on certain applications. You want the fastened elements to stretch but not so much that they permanently yield, plastic def.
"reduction in friction increases clamping force for a given torque" This makes sense to me, and I believe that is the point that everyone is trying to get across, but I still think that the most important thing is to have wheel studs that are in good shape, and follow proper torque specs. Anti-Seize in and of itself is not going to cause a lug nut to fly off, it will make it easier for a jackass with an air impact who isn't paying attention to stretch a stud, and it will also make it easier for me to take my lug nuts off and inspect things often to make sure that everything is safe.
My local WalMart puts a something ( never looked close to see what it is, has a copper color ) ( family car ) on the studs, torques the nuts, drives the car around in a circle and torques them again. 250,000 no problems. On my hobby cars I usually put a dab of grease on the studs. Tighten till my elbow clicks. Haven't had a problem in 45 years.
I had to put a little grease on my studs for my situation but wouldn't recommend it. Brand new rotors and new mag wheel lugnuts, I had one lugnut gall up on the stud when I tried to remove it so a little lube was in order. I ended up able to get to the backside of the rotor and weld the stud to the rotor to keep the stud from spinning to get it apart.
i usually use a drop of motor oil on the nut before i put it back on. No problems----yet. But, the question i have is, isn't most of the torque resistance when the nut touches the wheel, not so much the nut turning on the lug? Remember we are only talking 35-40 ft/lbs. here; i don't think this is going to damage/stretch a lug.
I don't know what cars your working on for only 35-40 ft lbs. Anything new I work on is at least 80 on up to 150 ft lbs and more .
Maybe if your studs are 3/8", but 1/2" X 20 (Ford, etc) specs are 80-100 ft. lbs., GM 7/16" would be around 70 ft.lbs.