Lowering Springs on Stock (OEM) Shock Absorbers

Quite often we’re asked about our lowering springs and if it’s okay to use with factory shock absorbers, or OEM, or even OEM replacement shock absorbers.

S.TECH Lowering Springs installed on 2017 Honda Civic Si factory (OEM) struts

The easiest answer is yes, especially if they’re actual OEM factory shock absorbers. We can say yes as well for aftermarket replacement shock absorbers, but there is somewhat of a caveat. The issue is with the spring perch on shock absorbers or struts that have them. For our ENDURAPRO & ENDURAPRO PLUS premium replacement shock absorbers, we use 3D modeling of actual OEM shock absorbers to make our spring perches, then just modify the design so that it fits over our larger bodied shock absorbers. However, there are some instances where we make modifications for increased strength where we feel it may be necessary. This 3D modeling allows us to make very exacting designs so that it will work with OEM coil springs. And with that, we make sure that our S.TECH and HIGH TECH lowering springs have very similar designs for top and bottom coils to match the OEM coil spring.

Why we say there’s somewhat of a caveat with using our lowering springs on other aftermarket shock absorbers is because we’re not too sure how they model their spring perches. Some may use 3D modeling or a mold to create a negative simliar OEM type spring perch. However, we have seen some differences between some aftermarket replacement shocks and the OEM shocks they’re supposedly modeled after.

S.TECH Lowering Springs installed on 2019 Mazda Miata factory (OEM) shock absorbers.

Besides the design of the spring perch (if applicable), our lowering springs are not intended to be very aggressive in terms of spring rate. This is intentional, as we expect that many customers are planning on installing our lowering springs onto OEM shock absorbers. With that, we have to keep in mind the OEM shocks damper valving and whether or not it can handle a specific spring design.

Another unknown variable with aftermarket replacement shock absorbers is how they’re valved in comparison to their OEM counterpart. Referring back to our ENDURAPRO & ENDURAPRO PLUS shock absorber line, we decided to “optimize” damper valving. Now, this optimization may vary by vehicle model. But it most cases we’re actually increasing damping force (slightly stiffer). Again, there’s a bit of a variable, because we may increase/decrease compression or we may increase/decrease rebound damping force, or a combination of both. There’s no set method of how we decide to valve. In some instances we may actually decrease damping force, especially compression, if we feel the ride quality will benefit from that change. But for other aftermarket replacement shock absorbers, we cannot say the same thing. In fact, when we’ve tested some aftermarket replacement shocks to their OEM counterpart, we’ve wondered why some of these aftermarket shocks are quite a bit softer (we’ve yet to see the opposite- stiffer than OEM). This can pose some interesting results in ride quality when comparing certain aftermarket replacement shock absorbers with our lowering springs, regardless of them not being very aggressive.

We’re not necessarily trying to pitch our ENDURAPRO or ENDURAPRO PLUS shock absorbers (how can we resist, though?!). But just know that ideally an OEM shock absorber will suit you best since that is what we designed our lowering springs to work with.

TEIN ENDURAPRO/PLUS SPRING KIT

High Performance Premium Shock Absorbers and Lowering Springs

Although we’re well-known mainly for producing coilover kits, the ENDURAPRO and ENDURAPRO PLUS shock absorber line is gaining more momentum stateside. While much more popular overseas, our premium replacement shock absorbers are starting to generate interest in a lot of consumers, especially if you’re on lowering springs and are looking for suitable performance shocks to pair with them, or you simply don’t want to invest in a complete coilover kit.

At the launch of the ENDURAPRO/PLUS line in the U.S., we also launched the ENDURAPRO Spring Kit and ENDURAPRO PLUS Spring Kit, which pairs our S.TECH lowering springs along with either of the shocks, depending on if you want fixed damping setting or 16-click adjustable damping.

Let’s take a look at what’s included with a ENDURAPRO Spring Kit (part # VSQ54-A1SS2) for the FR-S/86/BRZ.

Conveniently packaged, springs are placed over each shock absorber to minimize packing space and package dimensions. Quite honestly, there isn’t much to it. For certain vehicle applications, other components may be included, such as dust boots or bump stops. Although the ENDURAPRO/PLUS shock absorbers utilize our internal Hydraulic Bump Stoppers (H.B.S.), you will still need to retain either a OEM or TEIN bump stop, which is used as a precautionary measure.

Springs packaged over shocks to minimize packaging size.

Hard to tell from the photo, especially when it’s not lined up against an OEM or OEM replacement shock absorber, but our ENDURAPRO/PLUS shock absorbers are much larger in diameter to and OEM/OEM replacement. In fact, it really is just like one of our coilovers, just minus the threaded adjustment for ride height.

Valved to provide far better handling performance, our ENDURAPRO/PLUS shock absorbers are a perfect enhancement for an otherwise stock vehicle. However, paired with one of our lowering springs and you have a much more sporty ride that you can appreciate. We recommend this type of setup for customers who can do without ride height adjustability or pillowball upper mounts (although it may be compatible with some aftermarket pillowball mounts). That just means less maintenance (you are periodically inspecting your suspension, aren’t you!?!?!?!).

Currently our part numbers for ENDURAPRO Spring Kits and ENDURAPRO PLUS Spring kits are rather limited. However, we’re also still working on either developing performance replacement shocks or lowering springs for certain vehicle applications. If you have any questions about these products, please feel free to contact us at 562-861-9161, or reach out to any of our authorized dealers!