What motor mounts do and why they wear out
Motor mounts are rubber-and-metal pieces that hold your engine to the frame while letting it move slightly when you accelerate or brake. Over time — usually between 5 and 10 years — the rubber cracks, hardens, or separates from the metal, and the engine starts to shift too much inside the bay. You'll notice excessive vibration in the steering wheel or cabin, clunking sounds when you shift gears, or the engine visibly rocking when you rev it in park.
Replacing them is a straightforward job if you have basic tools and a way to support the engine safely. The process takes two to four hours depending on which mounts have failed and how accessible they are on your vehicle. Most people can do this in a driveway or garage without a lift, though a jack and jack stands are essential.
Key Takeaways
- Motor mounts hold the engine in place and absorb vibration; worn ones cause shaking, clunking, and visible engine movement.
- You will need a jack, jack stands, basic hand tools, and a way to support the engine weight while you remove the old mounts.
- The job involves raising the vehicle, removing the engine oil pan or skid plate, unbolting the old mounts, and bolting new ones in place.
- Most vehicles have between two and four motor mounts; check your service manual to find which ones are accessible from underneath.
- Tightening bolts to the correct torque specification prevents future movement and noise.
Gather your tools and parts before you start
You will need a socket set, wrenches, a jack rated for your vehicle's weight, jack stands, and blocks of wood to support the engine. Some mounts require a pry bar or engine hoist to lift the engine slightly while you work. Buy the replacement mounts from a parts supplier — they come as individual units or sometimes as a kit for all mounts on your vehicle.
Check your vehicle's service manual to identify which mounts you are replacing and their torque specifications. Different mounts on the same vehicle often have different bolt sizes and tightening requirements. Having this information before you start prevents mistakes and ensures the engine sits correctly when you're done.
Lay out all tools and parts on a clean surface so you don't lose small bolts or washers. Take a photo of the old mount before removal so you can see how it was oriented.
Raise the vehicle and support the engine safely
Park on level ground, engage the parking brake, and place wheel chocks behind the rear wheels. Locate the engine's lifting points — these are reinforced bosses on the block or cylinder head designed for this purpose. Never lift the engine by the oil pan, intake manifold, or any other component not designed for it.
Raise the vehicle with the jack under a frame rail or designated jacking point, then place jack stands under solid frame points on both sides. Lower the vehicle onto the stands and remove the jack. Use a second jack or engine hoist to lift the engine slightly — usually just an inch or two — to take weight off the mounts you're replacing. Place wooden blocks under the engine as a safety backup so it won't fall if the jack fails.
Do not work under the engine supported only by a jack. Jack stands and wooden blocks are your safety net.
Remove the old motor mounts one at a time
Start with the most accessible mount. You may need to remove the engine oil pan, plastic skid plate, or splash shield to reach it. Unbolt the mount from the engine block or bracket, then unbolt it from the frame or subframe. Keep all bolts and washers in a small container so you don't lose them.
Inspect the bolt holes on both the engine and frame for damage or stripped threads. If a hole is stripped, you may need to use a larger bolt with a washer, or drill and tap the hole for a new size. Check the frame mounting point for cracks or rust; light surface rust can be cleaned, but deep corrosion or cracks mean the frame itself needs repair.
Repeat this process for each mount that needs replacement. Some vehicles allow you to replace all mounts in one session; others require you to lower and re-support the engine between mounts to access different areas.
Install the new mounts and torque all bolts
Position the new mount so the bolt holes line up with the engine and frame. Insert bolts by hand first to make sure they thread smoothly — forcing a bolt can strip the hole. Once all bolts are hand-tight, use a torque wrench to tighten them to the specification in your service manual.
Tighten in a crisscross pattern if there are multiple bolts on one mount, similar to tightening wheel lug nuts. This ensures even pressure and prevents the mount from tilting. Do not over-tighten; exceeding the torque spec can crack the rubber or strip the bolt.
After all new mounts are installed and torqued, lower the engine back onto them by releasing the jack or hoist slowly. The engine should settle evenly without tilting or shifting to one side. If it doesn't, stop and check that all bolts are fully tightened and seated correctly.
Reinstall covers and lower the vehicle
Reinstall the oil pan, skid plate, or splash shield that you removed to access the mounts. Tighten these fasteners to their specifications as well — they protect the engine and direct airflow for cooling.
Raise the vehicle slightly with the jack to remove the jack stands, then lower it fully to the ground. Remove the jack and wheel chocks. Start the engine and let it idle for a minute while you listen for any unusual clunking or vibration. Gently rev the engine a few times in park to confirm the mounts are holding the engine steady.
Take a short test drive on a quiet road, accelerating and braking gently to feel whether the vibration has stopped. Excessive shaking should be gone, and gear shifts should be quieter. If you still hear clunking or feel significant vibration, stop and recheck that all bolts are tight and that you installed the mounts in the correct orientation.
Common mistakes and how to avoid them
The most frequent error is not supporting the engine properly before removing mounts. A falling engine causes serious injury and damage. Always use jack stands and wooden blocks, never rely on a jack alone. Another common mistake is over-tightening bolts, which cracks the rubber and defeats the purpose of the mount. Use a torque wrench and follow the manual's specification exactly.
Some people install mounts upside down or backward, which causes the engine to sit at the wrong angle and creates new vibration problems. Take a photo of the old mount before removal and compare it to the new one. The rubber should face the same direction, and any brackets or ears should align with the frame attachment points.
Forgetting to reinstall the oil pan or skid plate is also common and leaves the engine exposed to road debris and water. Before you consider the job done, verify that every cover and fastener you removed has been put back and tightened.
Frequently Asked Questions
Can I replace just one motor mount, or do I have to do them all?
You can replace individual mounts as they fail, but if multiple mounts are worn, replacing them all at once prevents future vibration and uneven engine movement. If you're already under the vehicle, it's often worth doing them together to avoid repeating the work in a few months.
What if I don't have a torque wrench?
A torque wrench is the correct tool for this job because over-tightening or under-tightening causes problems. If you don't own one, borrow or rent one from a tool library or auto parts store. The cost is small compared to fixing a damaged engine or frame.
How do I know if a bolt hole in the frame is stripped?
A bolt that spins freely without tightening, or one that tightens but pulls out easily, indicates a stripped hole. You can repair it by drilling the hole larger and using the next size bolt up, or by using a threaded insert kit designed for the original bolt size. Your service manual or a parts supplier can advise which repair is correct for your vehicle.
Do I need to replace the bolts, or can I reuse the old ones?
Reusing old bolts is usually fine if they're not bent, cracked, or stripped. However, some manufacturers recommend new bolts for safety-critical fasteners. Check your service manual; if it specifies new bolts, buy them. The cost is minimal compared to the job's total expense.
What if the engine still vibrates after I replace the mounts?
Verify that all bolts are torqued to specification and that the mounts are installed in the correct orientation. If vibration persists, the problem may be worn engine bearings, a bent crankshaft, or an imbalanced flywheel — issues that require professional diagnosis. Have a mechanic inspect the engine if new mounts don't solve the problem.