The hardware kit I got from AMK for the transmission cross member came with lock washers instead of lock nuts.
The assembly manual shows lock nuts.
Few questions.

1. Is there a big difference in the application of lock nuts vs lock washers with standard nuts.
2. Is the standard lock nut from the hardware store sufficient?
3. Am I overthinking it and either would work fine?

 

Yes, you are over thinking it. A lock washer will work fine, or you can buy lock nuts locally if you prefer.

 

My feeling is that lock nuts don't take heat as well as lock washers, but both should work as well in your application... Tedd

 

Since it's not visible maybe 1/2 & 1/2, check periodically and see if there's a problem.

 

I don't see an issue with either locknut or washer.

 

I think it depends, is the lock nut the type that doesnt use plastic, those are probably the best. Does the lock washer sit up against a slotted or enlarged hole it may not be as effective. Are you and me overthinking this….probably!

 

A trans crossmember doesn't get hot enough to negate using a stopnut. That's what i would choose. More difference in quality of stopnuts than between them and a lock washer. My mother worked at "Elastic Stopnut", I believe, the inventor of the type., back in the 80's. They had a full time employee, who went all over the country, to defend the use and name. Almost every time there was a lawsuit against the company, he just produced the documents to show that the failed stopnut was not one of their own, but a generic low quality one. Sad, too, as some of the cases involved boat props coming loose, and flying off, and hurting/killing people. Never one of theirs, though.

 

I don't really use the term locknut, I'll typically say nyloc. A car manufacturer will typically use neither, they tend to weld nuts to the brackets and make them captive. There are actually a few hundred 2006 Camrys driving around that have a bracket with nuts welded on by me using a real cool thing colloquially called a nut welder during my training program where we worked on various lines for a while.

If I were you, I'd use lock washers, hex nuts, and red loctite for that application. Also matchmark the assembly and look at them occasionally.

 

I ended up using the all-steel lock nut.

 

Stover lock nuts are fine, the ones you have in the first post are gr8.. Problem is you have to crank on them from start to finish.