How to Replace a Leaf Spring: A Step-by-Step Guide

A demanding but achievable home job. Here’s the full process — tools, safety, the critical steps and the torque figures — for vans, motorhomes and pickups.

So you’ve ordered a new leaf spring and want to fit it yourself. With the right tools, a bit of patience and a methodical approach, most people with some mechanical confidence can manage it at home. Allow two to three hours per side in an ideal case — though rusted bolts and a seized shackle can stretch that to six.

One note on scope: this guide is for vans, motorhomes and pickups. Heavy goods vehicles involve far greater forces and specialist tooling, so nothing here applies to them.

A broken leaf spring being removed.

Should you do this yourself?

It makes sense to take this on if you have some mechanical knowledge, a proper trolley jack and axle stands, somewhere solid and level to work, and the willingness to fight rusted fasteners. If you’ve never lifted a vehicle, don’t have the right equipment, are short on time, or your chassis is heavily corroded, hand it to a garage — and the same goes if you’re at all unsure about lifting safely. You can still save money there by supplying your own parts and paying only for the fitting.

On time: a clean job runs to about an hour to an hour and a half per side, a typical one to two or three hours, and a difficult one — seized bolts, rust-welded parts — to four to six. Plan for the middle of that range and you won’t be caught out.

Tools and parts

For the essentials you’ll need a jack rated to at least two tonnes, a matching pair of axle stands and wheel chocks; a ratchet and socket set plus combination spanners covering 10–24 mm, with extension bars and swivel joints for the awkward points; and a torque wrench (60–150 Nm) — which is not optional, since it’s the only way to tighten the critical fasteners correctly. Add penetrating oil, a wire brush, a hammer and a drift. For when things seize up, an angle grinder, a propane torch and an impact wrench will save you hours.

On parts: always replace the U-bolts (two per side) and their nuts (four per side) — they stretch and weaken over their life. Replace the spring eye bolts, bushings or shackle bolts too if they’re rusted or perished, since you’ll have everything apart anyway.

🛒 Order everything before you start. The worst place to find a missing part is with the vehicle up on stands. You can order leaf springs, U-bolt kits and reinforcement kits, shipped across Europe, directly from our webshop. [Link]

Safety rules that genuinely matter

Never work under a vehicle supported only by a jack — jacks fail, and that’s not survivable. Always use axle stands, on a solid chassis point, on solid ground (concrete or tarmac, never soil, gravel or ice). Lift only at the manufacturer’s jacking points. Before you start, secure the vehicle: handbrake on, in gear or park, front wheels chocked on both sides. Wear eye protection and gloves, and work somewhere well lit and ventilated.

Preparing the vehicle

Park on solid, level ground and secure it as above. If you’ll take the wheel off, crack the wheel nuts loose now — just loosen, don’t remove — while the wheel can’t spin.

Then comes a step that’s easy to skip and expensive to regret: clean and soak the fasteners. Wire-brush the U-bolts and their four nuts, the front and rear spring eye bolts and shackle, the lower shock absorber bolt and the anti-roll bar bolt if fitted. Spray everything generously with penetrating oil and leave it for ten to fifteen minutes; if a fastener won’t move afterwards, give it another dose and more time. That patience is repaid many times over on a fifteen-year-old, road-salted nut.

Lifting the vehicle

Position the jack under a proper jacking point — a chassis rail or a reinforced section near the axle, never the sump, a brake line or a cable. Raise the vehicle only until the wheel is a centimetre or two clear, slide the axle stands into place beside the jack, and lower it gently onto them. Leave the jack in place as a backup, rock the vehicle to confirm it’s stable, and only then get underneath.

Removing the old spring

Start with the lower shock absorber bolt (usually 15–19 mm). Free this first, because once the spring is released the axle wants to drop and the shock would otherwise fight it — undo the lower mount only. If there’s an anti-roll bar, disconnect its lower bolt at the axle too.

From here the axle will drop noticeably, and if the wheel is off, one side can sink to the floor. Watch your brake lines and cables closely — the weight of the axle can tear them, and a split brake line leaves the vehicle undriveable. A rope or a second jack under the axle to control its descent is a sensible precaution.

Next, the U-bolts, which clamp the spring to the axle. Loosen their four nuts (generally 17–21 mm) a little at a time, alternately, like wheel nuts. Pull out both U-bolts and remove the clamping plate if fitted. If a nut is seized, heat it with the torch, tap it sideways with the hammer, try the impact wrench, and only as a last resort cut the U-bolt off with the grinder — you’re replacing them anyway.

Now the spring eyes. The front eye bolts to a chassis bracket; the rear mounts through a shackle. Spray both, then unscrew or drift out the front bolt (typically 17–22 mm) and the rear shackle bolt. If an eye bolt won’t come out — a common frustration — the trick that usually works is to raise or lower the axle slightly to unload the spring, after which it frees up. Failing that, drift it out carefully so you don’t damage the bracket, or apply heat.

The spring is now free. Work it back and forth and ease it out — and mind the weight, since a leaf spring can run from 15 to 40 kg. A second pair of hands makes this far safer.

Before fitting the new one, clean the spring seats: wire-brush the top of the axle, the centre hole the spring’s centre bolt locates into, and the brackets, down to clean dry metal. The centre bolt has to seat precisely, and trapped dirt or rust can push the axle off-centre or let the spring shift under load.

Fitting the new spring

Here’s the mistake that catches people out: if the spring is asymmetric (different arm lengths front and rear), it has a correct orientation, and fitting it the wrong way round causes a crooked axle, pulling to one side and uneven tyre wear. As a rule the longer arm faces forward, but confirm it against the other side, the handbook, or the centre bolt marking before you commit.

Lift the spring in, align the eyes with the brackets, and make sure the centre bolt drops into its hole in the axle. Fit the front eye bolt and the rear shackle bolt and start them by hand — but leave them loose for now (there’s a reason, below). If a bolt won’t go in, nudge the axle up or down and put a little grease on it.

Tapping the front eye bolt through the spring eye — start it by hand and leave it loose for now.

Now fit the U-bolts, having confirmed the centre bolt is seated and the spring sits square. Start all four nuts by hand, then tighten gradually and evenly: nip them all up lightly (10–20 Nm), go round again in a cross pattern (40–60 Nm), then torque to spec. As a rough guide for dry threads, an M10 nut wants around 75 Nm, an M12 around 130 Nm, and an M14 around 200 Nm — drop those by 10–15% if the threads are oiled.

Refit the shock absorber (around 60–90 Nm) and the anti-roll bar if removed (around 40–70 Nm). Before lowering, check underneath:

•      All bolts in and tightened, U-bolts torqued evenly

•      No brake lines or cables hanging or under tension

•      Shock absorber and anti-roll bar refitted

•      Wheel back on, if removed (nuts nipped up, final torque later)

Fitting the U-bolt.

Lowering and final torque

Remove the stands, lower the vehicle and remove the jack. Now torque the wheel nuts (around 110–140 Nm, star pattern).

This is also when those spring eye bolts you left loose get their final torque. With the vehicle on its wheels the spring is loaded in its natural position — exactly where the eye bolts should be tightened. Had you torqued them on the stands, the bushings would have been clamped in the wrong position and over-stressed in use. Re-check the U-bolt torque, and finish with a look over the job: nothing hanging, every bolt home, the spring central and the ride height even.

The new leaf spring installed and clamped to the axle with new U-bolts.

After the job

Take a gentle 5–10 km test drive first, listening for rattles and feeling for vibration or pulling to one side. Anything odd is your cue to stop and inspect.

Then the step that’s easy to forget: re-check after the first 500–2,000 km. U-bolts bed in and their nuts can loosen, so re-torque them, check the spring eye bolts, and confirm the vehicle sits at an even height on both sides. Five minutes here stops a small problem becoming a roadside one.

Frequently asked questions

How hard is it to replace a leaf spring at home?

Moderate. With basic mechanical knowledge and the right tools, expect around two to four hours per side.

Do I have to replace both sides at once?

No — most people do one side. On an older vehicle, doing both keeps the ride height balanced.

Do I really need new U-bolts?

Ideally yes. Old U-bolts stretch and weaken, and they’re cheap insurance against a repeat job.

Do I need a torque wrench?

Strongly recommended — it’s the only reliable way to know the critical fasteners are tight (generally 80–150 Nm).

What’s the most common problem?

Seized, rusted bolts and nuts. Penetrating oil and patience solve most of them.

Will I need a wheel alignment afterwards?

No.

Can I fit a reinforced spring at home?

Yes, the same way as a standard one — it’s just heavier to handle.

Need the parts?

We supply leaf springs, U-bolt kits, reinforcement kits and helper air-spring systems for vans, motorhomes and pickups, shipped across Europe. Not sure which spring fits your vehicle? Send us the details and we’ll help you get the right part first time.

🛒 Browse leaf springs and fitting kits in our webshop  [Link]

📩 Not sure what you need? Send us your vehicle details  [Link]