are U-bolts "one time" use?
 

i have searched the internet. too close to call. by my call, it is 50/50. some say they stretch, and can only be used once. other say, if you have enough length, reuse them.

i am talking about the u-bolts on my rear suspension (toyota tacoma, 2006). leaf springs. i have add-a-leafs, coming to me..and i forgot to order new u-bolts. i specifically asked the salesperson, "anything else?". nope, nada, zilch...

they are not that expensive, so maybe new hardware would be cool, but all the ones i find are a bit longer and will need to be trimmed, so they dont hang that low. silliness.

pelican braintrust has never steered me wrong.

Technically, yes, they are one time use items.
Realistically, no.

Since (I presume) you're going to be streeting this truck, or very mild trail riding, they should be fine re-used. If you're going to be doing hard offroading, then you should replace them.

The other problem is that add a leafs make the leafpack thicker, and the stock u-bolts might not be long enough.

I would run what you have (if they still fit), and keep an eye out for longer ones that are designed for Tacomas with extra leaves (I know some company somewhere makes them). Buy them when you find them, and replace your stock ones at that time.

Usually with u bolts once you ad a leaf you need longer bolts but with some you can get away with reusing the old u bolts.

Be careful, and torque them evenly, and to the correct torque, or the leaves WILL crack. Just ask how I know. My rule of thumb is you need the at least the diameter of the threaded part sticking up past the top of your nut. If the ubolt is 1/2 inch, you should have at least 1/2 inch sticking up past the top of the nut when fully torqued.