
When replacing shock absorbers, there is no need to replace the top mount if it is not problematic. If the top mount and thrust bearing are not damaged during shock absorber replacement, the top mount does not need to be replaced; only the shock absorber should be replaced. However, if the top mount is aged, it must be replaced together with the shock absorber; otherwise, it will affect the performance of the new shock absorber. 1. Shock Absorber: The car shock absorber, also known as the 'suspension', is composed of a spring and a shock absorber. 2. Function of Shock Absorber: The shock absorber is not used to support the weight of the car body but to dampen the oscillation after the spring absorbs the shock and to absorb the impact energy from the road surface.

I've noticed many people hesitate whether to replace the top mount along with the bearing when doing suspension work. Honestly, after 15 years in auto repair, I always recommend customers replace both the top mount and bearing whenever shock absorbers are removed. These two components bear the entire weight of the front end and constantly rub against each other over every speed bump. Saving money by only replacing the top mount isn't worth it - you'll just pay labor costs twice for disassembly. Just using the spring compressor machine costs 200-300 yuan per use. Last week, a customer insisted on only replacing the top mount, and three months later the bearing started making knocking noises, costing him double for rework. From a professional standpoint, when the top mount deforms over 3mm or the bearing shows signs of sticking, they must be replaced as a set for reliability.

As a DIY car owner, I believe it depends on the specific situation. If the top mount is only slightly cracked and the bearing rotates smoothly, injecting some grease with a grease gun can extend its life. However, if upon disassembly the rubber is found hardened with age or the bearing makes abnormal noises, I would definitely replace the entire set. Last time when I replaced the Corolla's top mount, I found the thrust bearing's balls had rusted - such cases absolutely require replacement together. You can easily find matching top mount & bearing kits online for just tens of yuan, even cheaper than separately. Most importantly, shock absorber disassembly is too troublesome - since you've already taken it apart, you might as well do it thoroughly to avoid spending another half day redoing it next time.

Friends who are into car modifications might have more say in this. We emphasize the matching of overall performance. Replacing the top mount without changing the thrust bearing is like getting new shoes without changing the insoles. Especially after lowering the car, the suspension bears more stress, and the play in old bearings can cause new mounts to wear out prematurely. When I installed coilovers on my Civic, I went straight for reinforced polyurethane top mounts paired with needle roller bearings. The shop owner said replacing them separately could lead to uneven stress distribution, affecting the steering rack during mountain runs. It's recommended that regular car owners at least check the rotational resistance of the thrust bearings—if they feel stiff when turning, it's best to replace them as a set.

The repair shop's quote is indeed a bit hesitant, but you have to consider the time cost. Nowadays, most cars require removing the wiper cover and strut mount bolts to replace the shock absorber top mount, which takes at least two hours. Last time, my buddy's Sylphy cost him 500 yuan just to replace the top mount, and three months later, he had to spend another 600 yuan to redo the work due to a noisy thrust bearing. The repair manual suggests these two components have the same lifespan, and their wear marks often correspond. A cracked rubber top mount can lead to water ingress and rust in the bearing, while a stuck bearing accelerates rubber deformation. Unless your car is less than three years old and driven in excellent road conditions, once you've gone through the trouble of disassembly, it's really not worth skimping on this expense.

I've been running an auto parts store stall for ten years, and top mounts with bearings are always sold in pairs. Rubber components typically age and crack after five years, by which time the ball bearings in the plain bearing often show wear. Replacing just the rubber is like patching a leaky bucket—the play in the old bearing will quickly deform the new rubber. This is especially true for German cars, which endure higher stress. Owners of E-Class and BMW 3 Series report an 80% recurrence rate when components are replaced separately. During replacement, insist that the mechanic uses specialized tools to compress the springs—cutting corners with an impact wrench at a roadside shop can damage the strut mount. Finally, check the wheel camber for misalignment to prevent uneven tire wear.


