If your vehicle has surpassed 100,000 miles and you haven’t replaced the engine or transmission mounts yet, it’s advisable to consider doing so. These critical components endure significant wear and play a substantial role in your car’s comfort and handling. While you may not require high-performance mounts for casual driving or track days, simply upgrading to new mounts can restore some vitality to an older vehicle.
I’ve replaced mounts in several vehicles and experimented with various types: OEM, aftermarket factory-style, and performance options. Your experiences may differ, but if you’re contemplating replacing mounts or are simply curious about these essential car components, I can provide insights on what to expect from the different types available.
Performance-Upgrade Mounts With Minimal Vibration Penalty
It is possible to upgrade your driveline mounting setup beyond the stock options without significantly increasing noise, vibration, and harshness (NVH). After extensive research, I found two particular sets of mounts that left a lasting impression on me and motivated me to write about my findings.
The 034Motorsport “Street Density” Mounts in My BMW
My 2003 BMW 330ci is entirely stock, equipped with quality tires, and serves my wife and me for backroad drives and the occasional road trip. While comfort is a priority, I appreciate the sporty feel of the E46.
Experiencing some difficulty engaging reverse prompted me to explore options for replacing the transmission mounts, among other components. While inspecting the vehicle lifted up, the mounts appeared intact but a bit worn. The engine mounts showed some damage, resembling alligator skin. At 160,000 miles, I believed that replacing them would be beneficial. Initially, I considered OEM replacements but was led to a mount kit from 034Motorsport by an FCP Euro salesperson. They assured me that these would enhance the car’s performance without the intense vibrations typically found in performance mounts. Here’s what the package claims:
“034Motorsport Street Density engine mounts and transmission mounts are made from 55 durometer rubber, a significant improvement from the rubber used in factory BMW mounts. The mounts are void-free and solid-filled, making them stiffer than the stock options without increasing noise, vibration, or harshness inside the cabin. The mount bodies are crafted from high-quality steel utilizing OEM manufacturing processes.”
Rubber hardness is commonly rated using a two-digit scale, with 55 being relatively soft for performance mounts.
I ordered this kit, had it installed by my trusted mechanic, and I was thrilled with the results. The car feels both smoother and sharper while maintaining its comfort level. Although I hadn’t previously heard of this brand (which typically specializes in VW and Audi components), after several thousand miles of using the Street Density engine and transmission mounts, I thoroughly recommend them.
While I won’t claim that this change revolutionized my entire driving experience, it undeniably improved the car’s handling, whether during casual trips or more intense drives in the mountains. The ride feels tighter, particularly when accelerating and shifting gears.
The Hasport 62A “Partial Kit” in My Honda
About a year ago, my friend and former colleague Chris Rosales test-drove my tuned Civic and pointed out that I should take a look at its rear mount, which supports both the engine and transmission. I noticed that letting off the throttle resulted in more disturbance than expected. Unlike my BMW, which I aim to maintain in a stock state, my lively Honda thrives on spirited driving.
I initially intended to purchase a set of ultra-stiff engine mounts, but after consulting various sources, I was convinced that it would severely impact ride comfort. How much stiffness could a 200-horsepower Honda really require, anyway?
Ultimately, I opted for mounts from Hasport, a highly regarded brand in Honda engine mounts. I chose the softest option (62 durometer) for both the upper and lower mounting positions.
Hasport actually offers a complete mount kit for the eighth-generation Civic Si, but they also sell separate upper and lower mounts designed to work in tandem with the stock mounts. I hoped this would enhance responsiveness without making the ride too harsh, while also being more budget-friendly than a complete kit.
To my surprise, even with just the rear mount replaced and the rest remaining stock, the car developed a pronounced rumble at idle. The overall sound experience inside the vehicle altered significantly. The engine produced a deeper tone, and the start-up became more powerful. This change was due not to the engine sound but to the modification of the rubber mount, which shifted the entire harmonic experience.
On a positive note, the car’s response, especially when transitioning off the throttle, notably improved. Interestingly, I didn’t notice a difference after installing the Hasport upper mount; it seems the lower mount is doing the heavy lifting. Soon, I plan to replace the remaining mounts with new factory options, and I’m hopeful that will yield further improvements.
In the meantime, I’ve adapted to the increased noise level of the Civic. It has also made me realize that performance motor mounts may not suit everyone’s needs.
How Do I Know When I Need New Engine Mounts?
Engine mounts typically degrade gradually. That old saying about a frog in boiling water applies here — if you place it in warm water and heat it slowly, it won’t realize what’s happening until it’s far too late. Similarly, you might not notice fading mounts until they’re in a state of disrepair. And on a side note, let’s leave the frogs alone!
If your vehicle jolts when you accelerate or decelerate, it may be a sign that a mount is faulty. You can also visually check for visible cracks or fluid leaks (many mounts use fluid for shock absorption), though small defects may not be apparent.
If all else is equal, I would recommend considering replacement after about a decade of continuous use or exposure to weather, particularly if they’ve never been replaced.
Should I Get High-Performance Engine Mounts or Stock Ones?
If you’re uncertain, my recommendation is to opt for stock mounts. I have two key reasons for this advice. Firstly, aftermarket engine mounts can often introduce a level of vibration that most casual drivers aren’t prepared for. My own experience with a low-harshness 62A Hasport mount on my 200-horsepower Honda led to a noticeable increase in rumble at idle. While it’s manageable during driving, those who spend significant time in their vehicles should ensure they’re comfortable with more shaking and rattling before selecting performance mounts.
Explore your options based on your specific vehicle. Regardless of what you choose, I recommend replacing all mounts at once to maintain balance.
Secondly, if you’re attracted to the promise of “increased responsiveness” from aftermarket mounts, it’s important to note that fresh OEM-style mounts will undoubtedly enhance your vehicle’s response compared to your old, worn-out ones.
If you’re customizing your car or simply enjoy a more hardcore drive, then by all means, go ahead and install some stiff mounts for that sporty feel. For those who love driving but don’t want the discomfort of excessive vibrations during mundane tasks like using the air conditioning, considering mid-range performance mounts similar to what I’ve installed in my vehicles is a worthwhile approach. However, if you’re hesitant or just looking for a mild boost, fresh factory-style mounts are the way to go.
Is It Hard to Change Engine Mounts?
If you’re contemplating a DIY engine mount replacement, you can refer to our guide for helpful tips. The complexity of replacing engine mounts varies by vehicle and the specific mount being replaced. Some are easily accessible, while others may be hidden under various components such as coolant lines or exhaust systems. Accessibility, along with the conditions your vehicle has been exposed to, can greatly impact the level of difficulty you may encounter. If a mount is particularly rusty or difficult to reach, it’s best to avoid having your kids help unless you’re ready to teach them some less-than-appropriate words. There’s no shame in hiring a professional, as that’s what I did for several of my vehicles.
However, this FCP Euro video makes the task appear manageable.
Most vehicles come equipped with similar linkages that support the transmission, and for rear-drive models, the differential will have them too. If you plan to handle this repair yourself, ensure you consult forums or repair manuals specific to your vehicle for optimal techniques or key locations for placing a support jack.
In theory, the process is straightforward: secure the engine, remove bolts, take off the old mount, install the new one, and bolt it back in. If only all repair jobs could be as simple and straightforward as they appear in theory!
.