Diesel Technic’s 10 workshop tips for leaf springs
Lee Harris, Parts Specialist at Diesel Technic UK & Ireland, recently sat down with colleagues Lars, Kevin and Niklas from the Parts Specialists team in Germany to talk all things leaf springs. The team has issued ten top practical tips for workshops on how to handle them, from identifying the correct replacement to avoiding common installation errors.
While the technology may be well-established, they say, getting the details right during maintenance or replacement is still critical – not just for performance, but for safety and long-term durability.
1. Check both sides
“Always assess the condition of both sides of the suspension,” say the Parts Specialists.
“If only one spring is replaced while the other is already worn, it can result in a slight lean due to the uneven load handling. Since older springs may have settled under repeated stress, replacing both when needed helps maintain balance and stability.”
2. Clean fixing holes
“Before fitting, clean the fixing holes for the bolts to ensure smooth threading. Dirt or residue in the holes can make installation more difficult and affect how the bolts sit. A clean surface helps ensure proper fitment during assembly.”
3. Match the spring exactly
“When replacing a leaf spring, it’s essential to use the same type as the original. Different spring designs are built for specific loads and using the wrong one can lead to handling problems, overloading, or even spring failure. Always check the number of leaves and the spring’s rated strength to ensure a proper match.”
4. Tighten after lowering
“Bolts should only be tightened once the vehicle has been lowered back onto its wheels – and must then be tightened to the torque specified by the manufacturer. This ensures the spring is installed in its normal working position and not under tension. Tightening while the suspension is unloaded can put stress on the spring and lead to premature wear.”
5. Keep springs clean
“Leaf springs should be kept clean to prevent corrosion. Dirt, mud, and road salt can accelerate wear between the spring leaves. Regular washing of the underside of the vehicle and the springs themselves with soap and water can help avoid the buildup of dirt and debris and extend service life.”
6. Use proper tools
“Always use the correct tools for assembly and disassembly. The wrong equipment can damage parts, compromise safety, and increase the risk of improper installation. Investing in the right tools saves time and avoids costly mistakes.”
7. Check the centre bolt
“Before fitting, inspect the centre bolt that holds the spring leaves together. It must be tight and undamaged. A loose or sheared bolt can cause the leaves to shift under load, affecting suspension alignment and potentially damaging surrounding components.”
8. Align the axle
“After repairing or replacing leaf springs, measure the axle alignment to ensure the wheels track correctly and are properly aligned. If misalignment is found, recalibrate the axle to restore optimal performance and handling.”
9. Adjust spring holders correctly
“Spring holders must be tightened to the manufacturer’s torque specification. They should not be left under tension after tightening. If needed, turn the nut back slightly after reaching the torque so that the spring holder is tension-free.”
10. Centre the steering
“For maximum safety, always turn the steering wheel straight ahead, in the direction of travel before you start any work on leaf springs.”
To support workshops further, the Parts Specialists at Diesel Technic have produced a dedicated PS Tips video on leaf spring construction and application. In it, Niklas takes a closer look at different spring types, including solid leaf spring packs commonly used in construction, and explain how they compare in terms of durability to air suspension.
DT Spare Parts offers over 250 leaf springs for a wide range of commercial vehicles, including DAF, Ford, Iveco, MAN, SAF, Scania and Volvo. These products are available via the Diesel Technic Partner Portal under the ‘Suspension’ section.
For vehicles with a combination of leaf and air suspension, such as those equipped with lift axles, DT Spare Parts also supplies a broad range of air springs. This allows workshops to find all suspension-related components in one place.
Lee Harris of Diesel Technic
Lee Harris added: “Whether you’re in the workshop or managing a fleet, having the right parts information at the right time makes all the difference.
“As the dedicated Diesel Technic Parts Specialist for the UK, I’m here to support your workshop with advice on DT Spare Parts, answers to technical questions, brand insight, and details on the Diesel Technic Premium Shop rewards programme. I’m out on the road, visiting workshops across the country.”
To book a visit or arrange an appointment, contact Diesel Technic UK & Ireland.
