BioMax
+1y
Originally posted by kr1s
used on panhard bars if not when torsional force is put on the panhard during axel articulation that panhard will "adjust its self" leaving you with your axel off center in the truck and a wobbles when you brake along also used on adjustable link bars as well for the same function
That is the obvious answer, but the whole answer...
Reason #1 Any threaded part that is not tight is considerably weaker than if it were tight. This is especially true if the part is being used in a bending load. This is pretty hard to explain, so please just trust me.
Reason #2 On an adjustable part such as a heim, tierod or threaded bushing, the part is almost always being used in tension and compression. The jamb nut or even a clamp type system (simillar to that used on most stock vehicles) not only keeps the part from going out of adjustment, but also eliminates any movement within the threads. That small amount of movement is bad, even if it is lubricated. Over time, that movement will work into more and more movement, eventually rendering the part unuseable.
Reason #3 Standard threads like those used on heims are not designed to be used as pivots, so the movement needs to be eliminated on a twisting part (like the single point of a wishbone). The threads are not finished nice enough and the tollerances are typically not that great. On top of that, most threaded bungs are not 100% thread engagement (look it up). There is a type of thread that is designed to pivot while carrying a load called ACME thread, but I havent ever seen it used on a heim or anything like that.
I hope this answers your questions.