I don't know if it is wise but I have seen jam nuts used on rat rods.
My trucks have fine thread u-bolts with deep nuts.

U-bolt stretch?
https://beattiespring.com/blogs/knowledge-center/the-biggest-u-bolt-question-we-get

Last edited by buoymaker; 02/07/2021 1:34 AM.

"Adding CFM to a truck will only help at engine speeds you don't want to use."
"I found there was nothing to gain beyond 400 CFM."