What struts do and when they need replacing
Struts are the shock absorbers and springs combined into one unit that hold up the front or rear of your car and keep the wheels on the road when you turn or hit a bump. Over time—usually between 50,000 and 100,000 miles, though this varies by driving conditions and vehicle—the fluid inside wears out and the metal rod gets tired. When that happens, your car bounces after bumps, dips hard when you brake, or leans too far when you turn.
You can replace struts yourself if you have basic mechanical skills, a jack, jack stands, and a few hand tools. The job takes 2 to 4 hours per side. If you are not confident working under a car or do not have the right tools, a mechanic can do it in 1 to 2 hours and charge between $300 and $800 per strut, depending on your vehicle and location. Many shops replace both sides at once to keep the car balanced.
Key Takeaways
- Struts typically last 50,000 to 100,000 miles and need replacing when the car bounces excessively, dips when braking, or leans hard in turns.
- You will need a jack, jack stands, a socket set, a spring compressor, and an alignment tool or a way to mark the original position before you start.
- The job involves removing the wheel, unbolting the strut from the steering knuckle and the top of the car, and installing the new one in reverse order.
- After replacing struts, your car should be aligned by a shop because the suspension geometry has shifted.
- If you do not have a spring compressor or are uncomfortable working under a lifted car, a mechanic is the safer choice.
Tools and parts you will need
Before you start, gather a socket set (usually 10mm to 18mm), a wrench set, a jack rated for your car's weight, jack stands (never rely on a jack alone), a spring compressor (this is critical—the spring is under extreme tension), a strut removal tool or a large adjustable wrench, and new struts matched to your vehicle's make, model, and year. You will also need a helper to steady the car or hand you tools, and a flat, level surface like a driveway or garage floor.
Buy the correct strut assembly for your car. Check your owner's manual or ask a parts store for the exact part number. Some struts come as a complete assembly (spring, damper, and mount together); others are sold separately. Complete assemblies are easier for a first-timer because you do not have to transfer the spring from the old strut to the new one.
Preparing your car and removing the old strut
Park on a level surface, set the parking brake, and loosen the wheel lug nuts before you jack up the car. Then jack up the car at the frame (not the bumper or suspension), place jack stands under the frame on both sides, and lower the car onto the stands. Remove the wheel and set it aside.
Locate the strut. On the front, it connects to the steering knuckle (the part that holds the wheel) at the bottom and to the car's body at the top, usually under the hood or inside the wheel well. Take a photo or mark the position of the top mount with a marker so you can align the new one the same way. Unbolt the bottom connection to the steering knuckle (usually two bolts) and the top connection to the body (usually three bolts). The strut will come free. Have your helper support it as you work so it does not fall.
Transferring the spring if you bought a separate strut
If you bought a strut without the spring attached, you will need to move the spring from the old strut to the new one. This is where the spring compressor becomes essential. Clamp the compressor onto the spring following the tool's instructions, tightening it slowly until the spring is no longer pushing on the top mount. Unbolt the top mount nut, remove the old damper rod, and slide the new one in. Reinstall the top mount nut and slowly release the compressor.
This step is dangerous if done wrong—a spring under compression can fly apart and cause serious injury. If you are not confident, stop here and take the old and new struts to a shop. Many shops will transfer the spring for $50 to $100 per strut, which is worth the safety margin.
Installing the new strut
Align the top mount with the marks you made on the old strut, or use the holes in the body as your guide. Bolt the top of the new strut to the car's body first (three bolts, usually 14mm or 15mm). Then line up the bottom of the strut with the steering knuckle and bolt it in place (two bolts, usually 17mm or 18mm). Tighten all bolts firmly but do not over-tighten—you can crack the mount or strip the threads.
Reinstall the wheel, lower the car onto the ground, and tighten the lug nuts in a star pattern (opposite sides alternately) to may support even pressure. Repeat the process on the other side if you are replacing both struts, which is recommended for balance.
What to do after installation
After you have installed new struts, take your car to a wheel alignment shop. Strut replacement shifts the suspension geometry, and misalignment will cause uneven tire wear and poor handling. An alignment usually costs $100 to $200 and takes about an hour. Many shops will do it the same day.
Drive the car gently for the first 50 miles to let the new struts settle. You may notice a slight difference in how the car feels—new struts are often firmer than worn ones. This is normal. If the car still bounces excessively, pulls to one side, or makes noise, return to the shop to check your work or the alignment.
When to call a mechanic instead
Do not attempt this job if you do not have a spring compressor, a safe place to work under a lifted car, or confidence in your mechanical skills. Strut work requires precision and safety awareness. A mistake can damage your suspension, cause the wheel to fall off, or injure you. A mechanic has the right tools, insurance, and experience to do it safely and quickly.
Also call a mechanic if the strut bolts are seized or corroded and will not budge, if the steering knuckle is damaged, or if you discover other suspension problems while you work. These complications are common on older cars and require specialized tools or parts you may not have.
Frequently Asked Questions
Can I replace just one strut or do I have to replace both?
You can replace one, but most mechanics recommend replacing both on the same axle (both front or both rear) at the same time. A single new strut will be firmer than the old one on the other side, causing the car to handle unevenly and wear tires differently. If budget is tight, do both fronts first—they wear faster than rear struts.
How do I know if my struts are actually bad?
The car bounces more than once after you hit a bump, dips hard when you brake, or leans sharply when you turn. You may also hear a clunking noise from the suspension or notice the car sits lower on one side. A mechanic can confirm by pushing down on each corner of the car—if it bounces more than twice, the strut is worn.
What if I do not have a spring compressor?
Buy or rent one from an auto parts store or tool rental shop for $20 to $50. Do not try to remove the spring without one—the spring is under 1,000 pounds of pressure and can cause serious injury. If you cannot access a compressor, buy a complete strut assembly (spring included) or have a shop do the work.
How long does alignment take after new struts?
Most shops complete an alignment in 1 to 2 hours. Some offer same-day service if you drop the car off in the morning. Call ahead to confirm they have an opening and ask whether they recommend a two-wheel or four-wheel alignment—four-wheel is more thorough but costs more.
Will my car be drivable right after I install new struts?
Yes, but drive slowly and carefully to the alignment shop. The car may feel different—new struts are usually firmer—and the suspension geometry is slightly off until aligned. Do not drive on the highway or at high speed until the alignment is done.