My u bolts are 5/8s grade 8 steel on my dart.
A semi truck shop made the for me custom for about 30 bucks each. I could tighten them untill my custom 9" collapses.
When the hot sticky slicks grab the road behind my 4.88 spool gear set i dont want to worry about my pinion pointing up, Shearing the pinion and sending my drive shaft into the car.
I can post some pics of a wrecked race car in our shop where this happened so... its not something i ever want to see again.
I wound never re use U bolts except maybe on a garden trailer...
