Destructive Lock Nuts Suck

Good to hear no serious damage or injury. What do you mean by a destructive locknut, It's not something I've heard of before. I wonder if it was poor quality hardware. I was reading recently about a guy that was rebuilding the diff and final drive in his car and decided to use new bolts for the CW fixing but they failed when tightened before he reach the correct torque, apparently made in Asia, he re-used the original ones in the end and no problems.

The u-bolts that came with the new axles came with the destructive style lock nuts.

-------------------------

Google isn't telling me what a "destructive" lock nut is.

I know you guys have to know what I am talking about. There is a type of lock nut that is dimpled or punched that partially mangles the threads when installed to lock it in place. These have square punch marks on the flat.

I know you guys have to know what I am talking about. There is a type of lock nut that is dimpled or punched that partially mangles the threads when installed to lock it in place. These have square punch marks on the flat.

Is this the type of nut

I know exactly what you're talking about and I hate them . Lock washers and LocTite work better and don't mangle the bolts . Like the bolts that hold the bed on my '86 GMC pickup . With almost 40 years of rust and road crud . I'd like you to meet my angle grinder ... because the last 4 are too close to the gas tank for the Blue Wrench .

You probably want a bronze or stainless steel Drake two-piece Lock Nut:

.

Joe Gwinn

Looks a lot like a 40 dollar solution for a 2 dollar problem , Joe ...

They are called a "prevailing torque" "top distortion" nut -or a "side distortion" nut. There are also "two way" locknuts Then there arer "gripco" "crownlock" nuts NONE of them are inherently "destructive" and all are considered "re-useable" There are also "stover" nuts and "FujiLoks"

All of these can be used in various temperature situations including under cowl in aircrafdt - while "nylock" and "fiberlock" are restricted in aviation - and should be used with caution anywhere higher temps are anticipated. The only "destructive" locknuts I've run into are stainless steel nuts - paricularly on stainless fasteners - sometimes even with anti-seize, which gall and microweld themselves together - - - - The square punch marks centered on the flats sound like possibly 2 ways. Not flanged nuts, right? What grade bolt? Using prevailing torque nuts designed for a higher grade bolt CAN make them "destructive"

I know you guys have to know what I am talking about. There is a type of lock nut that is dimpled or punched that partially mangles the threads when installed to lock it in place. These have square punch marks on the flat.

Looks a lot like a 40 dollar solution for a 2 dollar problem , Joe ... Snag

------------------------------------ I look for reliable methods using easily available hardware or auto store products, such as doubled nuts. If necessary they can be modified on the lathe or drilled for safety wire.

I look for reliable methods using easily available hardware or auto store products, such as doubled nuts. If necessary they can be modified on the lathe or drilled for safety wire.

----------------------------

However the thin jam nut may require a thinner wrench, if you have one.

The OP was complaining that nothing he tried really worked, causing danger to man and beast, and not so much about the cost of the hardware, and Drake Nuts are the gold standard. They simply don't shake loose. Finger tight causes noticeable locking.

Failing that, I'd try a thick nut and a jam nut tightened hard against one another. And Loctite don't hurt. I recall from a study I read that one puts the jam nut under the thick nut for best shake resistance. Lok-Mor may have the study I recall, or it was an old NASA study.

Joe Gwinn

Well, I didn't actually say that. Just that two of the nuts came off for no good reason. I did install regular Gr-8 nuts and lock washers with red Permatex thread locker to finish my adventure. Afterwards it made the trip up up to Globe/Miami over the mountains, down and back up through Salt River Canyon, and then on up and down the grades into Show Low. There I loaded a full size 3/4 ton diesel pickup and made the reverse trip braking and engine braking up and down some modestly steep inclines. Enough so that there were brake check areas and emergency runaway pullouts.

This morning I ordered a box of each of gr-8 lock washers and nuts. The cost of which was about the same (a little less) as the couple items I bought at the Tractor Supply store in Coolidge to make repairs. Before I make another such trip I'll be replacing all the lock nuts with regular GR-8 nuts and high strength thread locker. As near as I can tell the threads on the u-bolts are fine and they do not appear to have stretched, but of course I didn't clamp them up and measure them. Two of the original nuts just failed to hold. The new nuts did spin easily into place (which surprised me).

These are a pair of six ton axles and they were not cheap. They were just the closest to the correct size for the application that I could find.

I've got a fair amount of faith in liquid thread locker. I've used Permatex, Vibratite, and of course Loc-Tite brands with good results over the years.

I'm not opposed to more expensive solutions. I just don't think its necessary here. I did look at your link and I can see places it would be useful.

The OP was complaining that nothing he tried really worked, causing danger to man and beast, and not so much about the cost of the hardware, and Drake Nuts are the gold standard. They simply don't shake loose. Finger tight causes noticeable locking.

Failing that, I'd try a thick nut and a jam nut tightened hard against one another. And Loctite don't hurt. I recall from a study I read that one puts the jam nut under the thick nut for best shake resistance. Lok-Mor may have the study I recall, or it was an old NASA study.

Joe Gwinn

----------------------------------

The OP was complaining that nothing he tried really worked, causing danger to man and beast, and not so much about the cost of the hardware, and Drake Nuts are the gold standard. They simply don't shake loose. Finger tight causes noticeable locking.

Failing that, I'd try a thick nut and a jam nut tightened hard against one another. And Loctite don't hurt. I recall from a study I read that one puts the jam nut under the thick nut for best shake resistance. Lok-Mor may have the study I recall, or it was an old NASA study.

Joe Gwinn

---------------------------- I'd gladly use them if the customer specified and paid for them. As both the designer and the builder/repairman I used best practices in the design and whatever was available on site for repairs, such as first aid kit Iodine for thread locker.

True, not those words, but this:

"Somewhere on a long flat Southwest of Globe/Miami I glanced in the mirror to see one of the hooks for a front strap laying on the trailer deck. The strap broke where it went over the frame.  Fortunately I had left the winch cable tight or I might have lost the truck."

Losing the truck on the highway is likely to cause a accident, and maybe a double accident (the departing truck may go sidewise, destabilizing the truck pulling or carrying everything). Free-range rolling truck tires are bad enough. Bloodcurdling.

This would have terrified me for sure.

I would submit that compared to the cost of an accident, a few Drake Nuts are insignificant.

By the way, Drake Nuts were invented in the 1910s, US 1,271,449.

And the analysis I couldn't remember was published in July 1922, and did compare the Drake Nut with the thin jam nut with regular nut (with jam nut between the big nut and whatever is being clamped). Drake Nuts worked regardless, but the big nut and jam nut assembly would shake loose. But this was before Loctite; this ought to work. The distorted nuts were also analyzed, and didn't win.

Joe

I must add a correction. Pair of 6K (3 ton) axles. Not 6 ton. Net load with the payload of the truck (tongue weight on the goose neck hitch) is probably around 14K, but I only licensed the trailer for 10K.

Before rolling out of Show Low I told somebody who stopped to check if I was alright, "I am just double checking my load. I don't want the truck to come loose, fall down the side of the mountain, and take me with it."

In the grades I stopped at every brake check and a few other places to do a walk around feeling the hubs, tires, and the tension on each strap. I did leave the winch cable in place on purpose with the intent it was a safety backup if not necessarily a great one. I will do tie downs a little differently in the future as well. I ran a single strap on the front, which is strong enough, but when it parted except for the winch cable there was nothing keeping the truck from rolling back except a rather meager bit of friction from the parking brake. I guess the parking brake was a second safety in case the strap broke, and the winch clutch slipped. The truck had not moved. The straps in the back were still tight. When I resecured it I used two straps in the front like I probably should have to begin with. I've hauled equipment before using chains and its pretty common to cross secure with a single chain in the front and a single chain in the rear if it gos across more than one point on the piece of equipment. I had hauling chains and binders with me also, but there wasn't really a good place to route them and be sure of getting good tension with the chain binders. The straps slid over the frame in the small clearance that was available just fine.

I might also buy a new set of straps. Some of these have been around since I hauled my Hurco mill back from Hemet California in 2010. Actually I have some new straps, but they are the type with flat plate hooks intended for securing loads straight across. They would not have held properly for this type of load. I had lots of stuff with me for the haul.

On my first haul (another similar size truck) I had a wheel hub get hot enough to be painful to the touch on the run out running empty. I reset the castle nut tension and pumped some more grease into the easy grease zirc. It was fine, but I put my hand on it every time I got out of the truck just to be sure.

This was my second haul on these axles.

I've used this trailer on the old axles to haul my tractor and a few other things before.

For suspension bolts I like flanged locknuts. NEVER split lock washers!!. A serated nut with attached serated washer (LoxNut) is the cat's ass. WhizLock nuts are a close second - particularly when installed with medium lock-tite.

Fijilok nuts work very well on adjustable threaded linkage - better than NyLok Flanged side distortion or top distortion nuts work well too - particularly with medium lock-tite.

If you MUST use lock washers, Nord-Lock or Disk-Lock. Either one requires 50% more torque to remove than the install torque (torque stud to 100 lb/ft and it takes 150 to break it loose)