U-Bolts & Threaded Rod

Truckspring.com uses the finest quality SAE Grade 5 and SAE Grade 8 steel, to provide you the best quality threaded rod and u-bolts. All threaded rod manufacturing processes are ISO 9002 and QS-9000 certified, to ensure the best quality products.

Threaded Rod

Threaded Rod - Straight End

We stock Grade 5 threaded rod in the following diameters: 3/8", 7/16", 1/2", and 9/16" ranging from 6" in length to 40", depending on the diameter of the rod. We stock Grade 8 threaded rod in the following diameters: 5/8", 3/4", 7/8", 1", 1-1/8", and 1-1/4", ranging in lengths from 14" to 48", depending on the diameter of the rod.

To order, select the grade of threaded Rod you would like:

U-Bolts

We maintain a finished stock inventory of Grade 5 and Grade 8 u-bolt kits. Each kit includes 2 u-bolts, 4 nuts & 4 washers, and are available in semi-round, round, square, and forged top bends.

To order u-bolts, select the Grade and Bend you would like:

Round U-Bolt Grade 5
Round U-Bolt Grade 8
Square U-Bolt Grade 8
Semi-Round U-Bolt Grade 8
Forged Top U-Bolt Grade 8
Grade 5 Round U Bolts Grade 8 Round U Bolts Grade 8 Square U Bolts Grade 8 Semi-Round U Bolts Grade 8 Forged Top U Bolts


Custom Bent U-Bolts

If you do not find the u-bolt that meets your requirements, send us an email, or give us a call @ 1-800-358-4751. We have a Centermark bender which bends U-Bolts in a converging path and thus protects the critical shoulder area. We can custom bend u-bolts to your specifications, and in most cases, ship the same day.

Need Custom Bent U-bolts?

Call 1-800-358-4751 for expert advice on U-Bolts. Or send us an email. We're open (Eastern Time Zone):
  • M-F: 7am - Midnight
  • Sat: 8am - 1pm
Secure online ordering is available 24 hours a day, 7 days a week.

About U-Bolts

U-Bolts on many suspensions provide the force necessary to create what is called the center clamp. This provides the permanent tie between not only the spring leaves, but between the spring and spring seat as well. The clamp performs the following functions:
  • Attach the spring firmly to the axle seat
  • Prevent leaf breakage through the center bolt section
  • Prevent center bolt breakage due to shear

U-Bolt Grades and Applications

We have SAE Grade 5 and SAE Grade 8 ubolts. Your application will determine the grade of steel that you should use. Listed below are recommended applications:

SAE Grade 5
  • 1045 Cold Drawn Steel
  • Yield = 92,000 p.s.i.
  • Medium strength, pickup-trucks, some trailers, and medium duty trucks
SAE Grade 8.1
  • 1541 Modified Cold Drawn Steel
  • Yield = 130,000 - 140,000 p.s.i.
  • Heavy Duty Trucks, Heavy Duty Trailers
  • Air Lift axle applications
  • Grade 8 equivalent

U-Bolt Q & A

Q.  If I'm replacing a spring, can I re-use the old u-bolts?

A.  No, you should never re-use u-bolts. A properly installed U-Bolt stretches a little bit under torque. The results of this small amount of stretching and its effects on the U-Bolt threads and deep nut, lower a used U-Bolt's ability to sustain the required clamping torque.

Q.  Is torque important when I tighten u-bolts?

A.  You bet it is. The following are a list of common problems resulting from improperly torqued u-bolts:
  • looseness in seat area
  • excessive wear on chassis components
  • possible spring breakage
  • possible axle slippage and misalignment