U Bolts with Fitting Position Front Axle, Rear Axle for FORD FALCON XE, XF Wagon, Ute and Van

Nolathane U-bolts clamp the XE, XF Wagon, Ute and Van FALCON leaf spring pack firmly to the axle. They?re one of the simplest parts in a leaf spring suspension, but also one of the most important. The U-bolts hold the axle in the right place on the spring, carry braking and acceleration loads, and keep the spring?s centre bolt from shearing. If they stretch, loosen or corrode, the axle can shift on the spring, causing clunks, instability and expensive damage.

Leaf spring U-bolts are a service item that should be replaced whenever the springs are unclamped from the axle. They suit 4WDs, utes, vans, light commercial vehicles and leaf sprung trailers.

How Leaf Spring U-Bolts Work on the XE, XF Wagon, Ute and Van FALCON

On a leaf spring suspension, the axle sits either above or below the middle of the spring pack. Two U-bolts on each side wrap around the axle tube, pass down either side of the spring and through a clamp plate or spring seat, and are tightened with nuts. The clamping force holds the spring pack tight against the axle?s spring perch.

The spring?s centre bolt locates the spring on the perch, but it?s the U-bolt clamping force that actually stops the axle moving. When the U-bolts are tight, braking and acceleration loads pass through the friction between the clamped spring and the axle. When they?re loose, those loads go through the centre bolt instead, which can bend or shear it.

Why U-Bolts Shouldn?t Be Reused

When a U-bolt is tightened, its legs stretch slightly and the threads deform. That?s how it creates clamping force. Once a U-bolt has been tightened and then removed, it can?t be relied on to produce the same clamping force again. It may feel tight when refitted, but the spring pack isn?t held as firmly as it should be.

Reused U-bolts can lead to:

• The spring pack shifting on the axle under braking or acceleration
• A sheared or bent centre bolt
• Leaves spreading apart at the clamp
• The axle moving out of square, causing rear-end steer and tyre wear
• Clunks and knocks from the rear suspension

Fitting new U-bolts whenever the springs are unclamped is the safest approach.

When to Replace XE, XF Wagon, Ute and Van FALCON U-Bolts

Replace leaf spring U-bolts when:

• Fitting new leaf springs or a suspension lift
• Fitting lowering blocks or spacers between the spring and axle
• Removing the axle or differential for service
• Replacing leaf spring bushes in a way that requires unclamping the spring
• The existing U-bolts are rusted, cracked or have damaged threads
• A sheared centre bolt or shifted axle is found

Taller spring packs and lift kits often need longer U-bolts than the originals, so check the length whenever the spring height changes.

Benefits of New Quality U-Bolts

• Correct clamping force, keeping the axle firmly located on the spring
• Protection for the centre bolt and spring leaves
• Better stability under braking, towing and heavy loads
• Fewer clunks and less movement in the rear suspension
• Fresh threads and nuts that tighten accurately to specification

Types of U-Bolts

U-bolts are made in different shapes to suit different axle housings:

• Round-top U-bolts have a curved crown to wrap around round axle tubes
• Square-top U-bolts have a squared crown to suit square or flat-topped axle housings and some spring seats

They also vary in internal width, leg length and thread size. Each listing shows the dimensions and shape of the U-bolt so it can be matched accurately.

How to Measure Your XE, XF Wagon, Ute and Van FALCON for U-Bolts

To choose the correct U-bolt, measure:

1. Internal width: the distance between the inside of the legs, which must match the axle tube or housing.
2. Leg length: from the inside of the crown to the end of the thread. It must be long enough to pass through the spring pack, any spacer or block, and the clamp plate, with enough thread for the nut to engage fully.
3. Thread size: the diameter and pitch of the threaded legs, which must match the nuts and the holes in the clamp plate.
4. Crown shape: round or square, to match the axle housing.

Most leaf springs use two U-bolts per side, so a vehicle usually needs four in total for one axle.

Fitting and Torquing U-Bolts on Your XE, XF Wagon, Ute and Van FALCON

Fitting suits professional workshops and experienced home mechanics. As a general guide:

1. Support the chassis on stands and support the axle with a jack.
2. Work on one side at a time, removing the old U-bolts, nuts and clamp plate.
3. Check that the spring?s centre bolt head sits correctly in the axle perch.
4. Fit the new U-bolts and clamp plate, then start the nuts by hand.
5. Tighten the nuts evenly in a crossing pattern, a little at a time, so the spring pack is pulled down square.
6. Torque to the vehicle manufacturer?s specification.
7. Repeat on the other side and lower the vehicle onto its wheels.

Re-check U-bolt torque after the first short drive and again after the first few hundred kilometres, as the spring pack settles. Check them again at every service, especially on vehicles that tow, carry heavy loads or drive off-road.

U-Bolts for Trailers

Leaf sprung trailers, boat trailers and caravans rely on U-bolts just as much as vehicles do, and they often suffer more from corrosion, particularly when launching boats in salt water. Inspect trailer U-bolts regularly and replace any with rust, pitted threads or loose nuts. Match the internal width, leg length and thread size carefully, as trailer axles vary widely.

Choosing the Right U-Bolts for Your XE, XF Wagon, Ute and Van FALCON

Measure the existing U-bolts or the axle and spring pack before ordering, and allow for any lift, block or thicker spring pack. Our fitment guarantee means the U-bolts you order for your XE, XF Wagon, Ute and Van FALCON are confirmed to suit it.

Lifetime Warranty

Nolathane U-bolts are backed by a lifetime warranty against manufacturing defects in material and workmanship, for the original vehicle they?re fitted to.

Shop U-Bolts for Your XE, XF Wagon, Ute and Van FALCON

Replacement U bolts are found in Nolathane's leaf springs range, along with spring saddles to restore the axle seat.

Find the U-bolts for your XE, XF Wagon, Ute and Van FALCON or trailer, then order online with fast shipping or have them fitted by a Nolathane reseller. 60-day returns give you time if a part isn?t right, and our local support team can help you choose the correct size, whether you?re fitting new springs, servicing a working ute or replacing rusted trailer hardware.