Your truck vibrating more than usual on the highway? The rear end floating when you’re running empty? Tires wearing unevenly for no obvious reason? These are your suspension telling you something is wrong.

At Ressorts Industriels Laval / C.T. CAM, suspension has been our specialty since day one in 1971. We started with leaf springs. Here’s what five decades of suspension work have taught us about what breaks and why.

5 Signs Your Truck Suspension Is Failing

1. The Truck Leans to One Side

This is the most visible sign. Park on level ground and walk around to the rear: if one corner sits lower than the other, you’ve likely got a broken or collapsed leaf spring. On trucks with air suspension, a deflated or leaking air bag will cause the same effect.

2. Excessive Bounce After Bumps

A truck with healthy suspension absorbs a bump and settles quickly. If yours keeps bouncing several times after hitting a pothole, the shock absorbers are worn out. On Quebec roads, especially after spring thaw, worn shocks make every trip miserable and, more importantly, reduce tire-to-road contact.

3. Uneven Tire Wear

Tires wearing more on one side than the other, or more on the inside edge than the outside, often points to a suspension problem before it points to an alignment issue. A sagging suspension changes the contact angle between the tire and the road. The result is accelerated, uneven wear. On a heavy truck, a full tire change costs thousands of dollars. Suspension maintenance is directly tied to tire costs.

4. Clunking or Squeaking Over Bumps

Clunking sounds when you roll over a rough surface usually point to worn bushings, loose U-bolts, or a shackle with play in it. A persistent squeak is often leaf springs rubbing against each other without adequate lubrication between the leaves. Both mean components that need replacement before the problem gets worse.

5. The Truck Pulls to One Side

A truck that drifts without steering input can have its cause in the suspension, in the alignment, or in both. We have a full article on a truck pulling to one side that covers every possible source. On the suspension side, a failed air bag providing unequal support, or a broken spring causing the axle to shift, can both produce this behavior.

The Most Common Causes in Quebec

Broken or Collapsed Leaf Springs

Leaf springs carry the truck’s weight and absorb road impacts. Steel fatigues over time under repeated load cycles. Quebec roads, with their freeze-thaw cycles, potholes and road salt, accelerate this fatigue significantly. Broken leaves are among the most frequent repairs we handle at our Laval shop.

Worn Shock Absorbers

Shocks control rebound after the spring absorbs an impact. Once they’re worn, the spring oscillates freely. That’s the bouncing you feel. Beyond comfort, worn shocks mean reduced tire contact with the road surface, which affects braking and handling.

Cracked or Deflated Air Bags

On air-suspended trucks, the rubber air bags can crack, puncture or develop slow leaks. A deflating air bag drops that corner of the truck. If you notice one side settling lower when the truck sits overnight, a leaking bag is the likely cause.

Worn Bushings and Rubber Isolators

Bushings are rubber or polyurethane components that cushion the connection between metal suspension parts. They wear with age and mileage. As they deteriorate, the play they develop produces noise and instability. Replacing bushings is relatively inexpensive compared to what worn-through metal components cost.

Loose or Failed U-Bolts

U-bolts clamp the spring pack to the axle. If they loosen, the spring can shift position, which changes axle alignment. A broken U-bolt is a more serious situation where the axle can actually move under load. These are checked at every maintenance interval.

Leaf Spring vs Air Suspension: Key Differences

Criteria	Leaf Spring Suspension	Air Suspension
Reliability	Very high, few components	More complex, more parts
Ride quality	Firm and direct	Softer, better shock absorption
Load adjustability	Fixed	Adjustable to load
Repair cost	Lower	Higher
Component life	150,000 to 300,000 km	Air bags replaced more frequently
Typical use	Dump trucks, flatbeds, vocational	Long haul, refrigerated transport

The majority of the trucks we see in Laval and on the North Shore run leaf spring suspension in the rear. It remains the most common configuration for delivery trucks, dump trucks and commercial fleets in Quebec.

Suspension Repair Costs

Repair	Typical Price Range
Leaf spring replacement (one side)	$500 to $1,200
Shock absorber replacement (pair)	$300 to $800
Air bag replacement	$400 to $1,000 per bag
Bushing replacement	$200 to $500 per bushing
U-bolt set replacement	$150 to $350
Full suspension kit (one axle)	$1,500 to $3,500

Prices include parts and labour. The exact cost depends on truck make, suspension type and scope of work.

The most important thing to understand: a broken leaf spring left unrepaired damages the axle, the chassis and the tires. What would have been an $800 repair can become a $3,000 job if ignored.

Alignment vs Balancing: What’s the Difference?

This comes up often. Balancing is about equalizing weight around each individual wheel to eliminate vibration. Alignment is about setting the angles of all wheels relative to the chassis and to each other.

If your truck vibrates at highway speed, balancing is probably the issue. If it pulls to one side or tires are wearing unevenly, alignment is the likely culprit. And if your suspension is worn, neither fix will hold until the suspension is repaired first.

At our shop, we always inspect the suspension before performing a laser alignment. Aligning wheels on a compromised suspension is a waste of time and money.

Frequently Asked Questions About Heavy Truck Suspension

How do I know if it’s the suspension or the alignment causing the problem?

The quickest answer is to come in for a combined inspection. Generally: if the truck leans, bounces hard or makes noise over bumps, it’s suspension. If tires wear unevenly and the truck pulls, it’s often both. We check both systems together.

Can I drive with a broken leaf spring?

The truck will move, but it is not safe. The truck leans, tires wear rapidly and the chassis absorbs stress it was not designed to handle directly. A broken leaf spring is also an automatic SAAQ inspection failure.

How long does heavy truck suspension last?

Leaf springs on a well-maintained truck last between 150,000 and 300,000 km. Quebec conditions tend to push that closer to the lower end of the range. Shock absorbers typically wear out before the springs do.

Do you work on pickup truck suspensions too?

Yes. We handle suspension repairs for Ford F-150, RAM, Silverado and all pickups. Leaf springs on pickups wear the same way, especially when the truck regularly carries or tows heavy loads.

Which truck brands do you work on?

All of them. Freightliner, Kenworth, Peterbilt, International, Mack, Volvo, Hino, Isuzu and all others. We keep parts in stock for the most common models.