See full version: Can you reuse leaf spring U bolts
Jack up one side, put the truck on the jack stands and locate the damaged U-bolt that you would like to replace. Take off the nuts of the u-bolt and remove. Old, rusted u-bolts many need to be cut off. Place the new U-bolt around the leaf spring.
Likewise, why would u bolts have to be tightened correctly? If the U-bolts have been holding the spring so tightly to the pad that no movement occurs, there can be little wear. The U-bolt top plate is important for two reasons: It maintains the U-bolts directly in the line of pull and proper alignment with each other.
How tight should leaf spring U bolts be? [links]
Reinstall leaf springs and make sure the bolts are firm. Measure the height of the vehicle from the ground to the mid section of the car. Make sure the car is on a flat surface. Compare the results with the car’s service manual. Bounce the car up and down at the corners to stabilize the suspension before inspecting the vehicle’s height. more
Ensure that the lengths of the right and left rack ends are the same. Fasten the tie rod end lock nuts and take care not to use too much force. Replace the boots on the seats and reinstall the clips. [links]
Rear leaf springs are one of the components that make up the suspension system of a vehicle. They enhance on and off road performance, handling, and control. Failure to take care of such components can jeopardize the safety of the vehicle and its occupants. After aligning leaf springs make sure that the car is safe and controllable. This, however, should not be done on public or busy roads.
Check the condition of the leaf springs; looking for damage, wear and tear. If they are damaged, replace them with new ones. more
Why would u bolts have to be tightened correctly? [links]
Secondly, can u bolts be reused? Most recommendations are to drive the vehicle for 100 miles and then re-torque the U-bolt nuts. However, it seems factory OEM U-bolts are never re-torqued, certainly not after any significant amount of driving. Eaton springs recommends to "re-torque the newly installed u-bolts after 50 miles of driving. more
Tighten all U-Bolts until they are snug only. Tighten in the sequence shown to approximately 1/3 of recommended torque. Repeat, using the same sequence, gradually increasing the torque through a second and third stage until the recommended final torque is attained.
If you want to use a bolt as well as welding your leaf spring hangers, then you can follow the same torque specs as the leaf spring u-bolts. A 1/2 inch diameter bolts should be torqued between 45 ft/lbs and 70 ft/lbs. [links]
Additionally, how tight should leaf spring U bolts be?
If the U-bolts have been holding the spring so tightly to the pad that no movement occurs, there can be little wear. The U-bolt top plate is important for two reasons: It maintains the U-bolts directly in the line of pull and proper alignment with each other. [links]
The smallest amount of looseness or vibration in your U-bolts will allow for movement between your axle and leaf springs. If you have suspension blocks, this movement multiplies. Over time, a small amount of movement will almost always become a larger problem. It doesn’t take much movement before center bolt heads being to shear or you run the risk of warping your axle seats. We’ve seen this and much worse happen over the years as a result of reused U-bolts coming loose. [links]
U-bolts are a torque to yield bolt. This means when you tighten down a U-bolt to its proper torque spec, the bolt stretches to achieve that level of tightness. While the U-bolt has some flexibility in its ability to stretch after being loosened, the bolt will never tighten enough to allow it to regain its full torque spec potential. more
Why can’t I reuse my U-bolts?
A high-quality U-bolt will be made of high-grade hardened steel and have rolled threads instead cut threads. Rolled threads offer a larger diameter than the shaft of the bolt, resulting in more core material and strength. Lower quality U-bolts are often made with cut threads which are just cut out of the shaft of bolt resulting in less material thickness. Cut thread U-bolts are never a good idea to use because the threads tend to strip. Additionally, this means the U-bolts won’t be able to achieve near the torque spec that a rolled thread U-bolt can. [links]
This is one of the single most commonly asked questions out there when discussing leaf springs and related components. We get a variety of reactions when we advise our customers that reusing U-bolts is never a good idea. There are some very specific reasons why we stress this point so much, trying to sell you something you don’t need is not one of them.
Another consideration to bear in mind when talking about U-bolts is ensuring you use both high grade, high quality U-bolts as well as using the correct size U-bolts for your application. We often encounter loose axles and damaged suspensions due to the U-bolts simply being the wrong size. [links]