I found this interesting.
Lock Washers
- Thread starter Trav
- Start date
- Status
They do address it.
The point of antisieze in critical applications is not for ease of removal of fasteners. It has more to do with installation.
AutoMechanic
Site Donor 2026
Interesting those ones they referred to as spring washers I’ve always learned and seen labeled as lock washers. I sure do learn a lot from you Trav and I appreciate it.
Very informative vid
I can see how the “lock” washer is called a spring washer it does resemble a wedge of a coil spring.
I always thought anti-seize main function was for the ease of removal or disassembly. Well similar to pipe dope, pipe dope definitely eases assembly and installation it’s amazing how many more turns you can get using pipe dope.
I can see how the “lock” washer is called a spring washer it does resemble a wedge of a coil spring.
I always thought anti-seize main function was for the ease of removal or disassembly. Well similar to pipe dope, pipe dope definitely eases assembly and installation it’s amazing how many more turns you can get using pipe dope.
This kind of information confounds me, as it should anyone with OCD. I still see lots of new equipment put together with the traditional split ring lock washers. Why, if they are not effective? Why are we not being educated more openly about these better lock washers? Is this a non-problem except in very critical situations?
I wonder how these washers affect torque wrench readings, which are very susceptible to friction differences?
Certainly we must have some engineers here to explain this conundrum.
I wonder how these washers affect torque wrench readings, which are very susceptible to friction differences?
Certainly we must have some engineers here to explain this conundrum.
Last edited:
JHZR2
Staff member
Me too. Every Mercedes Ive had used double nuts on the rear shocks, and they have been hard to remove. I’d think that shocks would be a good chance for vibration and chances to have a bit of up-down motion that could cause them to come apart…
Looks like a really good, simple design, like 2 external tooth lock washers joined by wedged ramps inside. Almost wonder how external tooth lock washers would do compared to the rest, since they dig into both surfaces as well.
Cool vid, I'd always heard that a 'lock' washer didn't do much good unless it bit into the materials. You can clearly see in that vid where it is peeling back material where it made contact. Guess that shows it doesn't really matter.
JHZR2
Staff member
That was a good video. I wish they would have shown the tooth type lock washer and the nuts that have some “teeth” on their flange.
But all that said, what went through my mind first was, is the Junker test relevant? How many cars go hundreds of thousands of miles with certain fasteners untouched and tight? What about other stuff in other applications, may be permanent with no issue?
Maybe in a safety critical/mission essential application, this matters, but in other applications, like most everything most of us encounter, does it?
But all that said, what went through my mind first was, is the Junker test relevant? How many cars go hundreds of thousands of miles with certain fasteners untouched and tight? What about other stuff in other applications, may be permanent with no issue?
Maybe in a safety critical/mission essential application, this matters, but in other applications, like most everything most of us encounter, does it?
Wow that is cool 
Tesla uses quite a few Nord Locks on suspension parts. Pretty cool tech.
I saw some Junker data on wedge-lock washers, an anaerobic threadlocker, serrated washers and spring-lock washers. From best to worst, this was the order of finish. No brands were specified. The best solution probably should include the correct amount of a good thread lubricant and a retorquing program. I don't know but I would expect the wedge-lock performance might diminished after being retorqued although they seem to maintain clamp force and might not require retorquing very often, if at all.
I think the video is demonstrating crazy levels of vibration - way more than any road vehicle would see. I've probably only seen 2 or 3 instances where a bolt or nut loosened up from vibration. One had a spring lock washer. A little blue Loctite and a proper torque cured it.
Anything that is critical to safety should be locked with some type of bend-over metal tab (like used on motorcycle rear sprocket nuts) or similar, or lock wired. Lots of fasteners are lock wired on critical aircraft hardware.
These special lock washers would be a good alternative if a mechanical locking system (lock tabs, safery wire, etc) isn't well suited.
Last edited:
There are occasionally fasteners that tend to come loose on some engines usually where mix metal parts meet eg thin steel header flanges. Machinery and motor cycles especially old Brit and HD really can benefit from these.
The shocks have rubber mounting to absorb vibration, if the didnt it would be a very unpleasant ride.
JHZR2
Staff member
No doubt there are places these can be used with benefit. Fortunately I haven’t had to deal much with backing out on vehicles. OPE and other applications I have.
Point taken on the rubber under the dual nut, it provides positive upward pressure on the two. But other approaches that put upward pressure on the nut (spring/split lock washers as an exsmple) didn’t help In the video.
The way I understand it the vibrations that cause fasteners to loosen as shown in their video are transverse vibrations and not longitudinal as would be produced by say a shock.
I do use these occasionally where the fasteners tend to come loose and loctite or wiring will not work for some reason eg high temp or inconvenient location eg exhaust to manifold flages where the gasket (even MLS ones) has a repeatedly short lifespan.
Your point about OPE is exactly why I mention old bikes and machinery that create a lot of non dampened vibrations. these are the kinds of subjects that I find very interesting.
I do use these occasionally where the fasteners tend to come loose and loctite or wiring will not work for some reason eg high temp or inconvenient location eg exhaust to manifold flages where the gasket (even MLS ones) has a repeatedly short lifespan.
Your point about OPE is exactly why I mention old bikes and machinery that create a lot of non dampened vibrations. these are the kinds of subjects that I find very interesting.
+1 Absolutely, way more than would be experienced in normal service for most vehicles but I like the point they are making which as far as can tell is some of the methods we have been using for decades to prevent loosening are just not as good as we thought they were when subjected to situations that would cause them to loosen anyway.
At the cost of these things I am not going to be replacing every flat washer and I never use split washers anyway but for the few real problem fasteners its worth it.
- Status
