Recently purchased 3 1/4" rear leaf spring blocks and new U-bolts to replace the 2" blocks on my '23 F250. It had barely 3/8" of rake in the rear and being that I tow on a regular basis I wanted a little more rake so there'd be less sag.

Dealership quoted told me about 3.5 hours, so $500 which I thought was ridiculous. A local Spring and chassis shop told me less than an hour so maybe $100. When I dropped it off this am I had printed out what I could find regarding U-bolt torque spec which was tightening in a cross pattern to various ft lbs and with a final torque of 195. When I showed the guy at the shop he brushed it off and said "tight is tight". I kind-of had to chuckle. He did mention that technically I should've given them new lock-nuts as well with the blocks and U-bolts bu that it shouldn't be an issue to re-use the old ones.

New U-bolts would only be about $40 and now that the new blocks are installed it would be pretty easy for me to swap them out in my driveway and torque properly if necessary.

How important is the torque spec and/or new lock-nuts? Should I swap them out or am I overthinking it.

 

I’d drive the thing. Techs at a spring shop have tightened enough of these to know what they’re doing.

 

Rear U-bolt torque= 2 grunts and a fart.
Call it good and don't look back.

 

tech was right on the new u-bolts and nuts, but I would reuse.

1/2 drive socket and bar and tighten it down tight enough it wont turn anymore. dont forget the loctite.

 

Use the German method, guedentiet.

 

Re torque after a 50-100 miles
reusing ubolts and nuts should not be a problem

 

U-Bolts Stretch along with the threads Suggest replacing both. Retorque is always good Idea.
We always use these, L&H threaded rods
https://www.lhrods.com

 

Do what you feel is right and makes you comfy.
As others have stated, reuse bolts/nuts, tighten until tight, etc... perfectly fine. Would you ever have an issue, probable not.
If it was me, there are torque spec for a reason, and also why not to reuse bolts and nuts.
For the $40 I would get all new, torque to spec, retorque, and know in my mind that if there ever was a failure, I
used new components and they were installed and torqued correctly.

 

grunt fart to the gutentite spec has always been solid for parts like that IMHO.

It's how i did my carli leaf springs 4 years ago.

 

No reason to need new lock nuts. If the threads are yielding inside the nut then it's over torqued.

 

After maintaining up to 3 race bikes for a few decades, I've learned to rely on my torque wrench - even seasoned mechanics can be way off doing it by feel. I'd just go over it with a torque wrench after the fact.

Dave