VW SEAT Strut Bump Stop 3C0412303C | OEM Replacement Supplier & Custom Manufacturer

VW SEAT Strut Bump Stop 3C0412303C - Front Axle Buffer Overview

The 3C0412303C is the front axle strut bump stop used across a wide range of Volkswagen and SEAT front suspension builds, and it is one of the most frequently requested 55 mm stop buffers in the VW Group spare part trade. Mounted over the piston rod of each front shock absorber, inside the dust cover and in the centre of the coil spring, the buffer takes over at the end of the compression stroke: once the spring and the damper approach full travel, it compresses progressively and converts the remaining impact into a controlled, cushioned load instead of a hard metal stop. Bonpora manufactures this reference under part number 4110111 in polyurethane and supplies it to distributors, suspension kit assemblers and workshop chains as a direct OEM replacement.

For trade buyers this part belongs to a family of VAG buffers that look nearly identical from the outside and differ mainly in working height. The 3C0412303C is the 55 mm front version, catalogued for Passat B6 and B7 builds without sport suspension, for Golf R models without adaptive DCC dampers, for Jetta builds without the GLI package and for SEAT Leon front struts. This page summarises the specifications, the verified fitment, the cross references and the custom manufacturing options.

What the 3C0412303C Strut Bumper Does in the Front Suspension

Volkswagen lists the component under several names in its own catalogues, including Suspension Strut Bumper, Buffer, Stop bumper, Stopper and Coil Spring Damper. All of these names describe the same elastomer body: the final stage of front suspension travel control. A polyurethane buffer of this type is formulated to be dense and progressive, so it absorbs the last part of the stroke when the coil spring alone would bottom out against the strut. Without a serviceable buffer, full-compression events pass directly into the damper rod and top mount and accelerate wear of more expensive components.

Three practical points matter for buyers. First, the 3C0412303C is catalogued for the front axle only, with two pieces per vehicle, and it is a symmetrical slip-on part, so there is no separate left or right article number to manage in stock. Second, it operates inside the dust cover, and most workshops inspect or replace the two components together, because a cracked cover lets grit reach the buffer and the damper rod at the same time.

Technical Specifications of the 3C0412303C Buffer

A short note on dimensions helps to avoid disputes at goods-in inspection. The VW catalogue assigns a working height of 55 mm to this reference, the febi aftermarket listing records an overall length of 57 mm with a width of 62 mm, and the Bonpora drawing measures 19.5 mm bore, 60.8 mm outer diameter and 55.4 mm height. These values describe the same buffer at different measurement points and tolerances, so height remains the decisive check.

Vehicle Applications - Which Models Use the 3C0412303C

European catalogue data links the reference to the Passat and Golf ranges and to the SEAT Leon, while United States dealer catalogues add the locally built Passat and the Jetta. The table below condenses the applications buyers verify most often.

The United States dealer catalogue adds useful trim-level detail. For the Golf R it specifies a 2.0 litre engine with all wheel drive and without DCC adaptive suspension, which excludes cars fitted with the electronic damper package. For the Passat it specifies the 55 mm front bumper for builds without sport suspension, and for the Jetta it lists the non-GLI models. Chinese trade listings for the same reference name the FAW-VW Magotan among front axle applications, and several European catalogues also assign the buffer to Ford Focus III builds.

Because the same body style can leave the factory with 55, 70 or 90 mm front buffers depending on suspension code, model and year alone do not guarantee a match. Buyers should confirm against the VIN or the suspension PR code before releasing a purchase order.

The 55 mm Height - Separating 3C0412303C from Related Buffers

The 412 303 numbering block covers a whole family of shock absorber buffers that share a similar cone shape and differ in height, bore and axle position. Height is the fastest sorting key, and the table below shows where the 3C0412303C sits inside the family.

Two conclusions follow for purchasing teams. A buffer ordered by outer diameter alone can fit the strut body and still be the wrong part, because the compression characteristic is set by height. And when a customer reports repeated bottoming out after a replacement, the first check is whether the fitted height matches the suspension code of the vehicle.

Aftermarket Cross-Reference Numbers for 3C0412303C

Independent aftermarket brands list the same buffer under their own article numbers. The following references are recorded against OE 3C0412303C in established catalogue systems.

Stocking against the OE number rather than against one aftermarket brand keeps the line interchangeable across all of these references, and it simplifies customer support when an enquiry quotes a febi or SWAG number instead of the VW original. Our auto parts catalogue lists the full strut bump stop programme organised by OE reference.

Signs of Wear and Replacement Guidance for the Front Buffer

Front buffers on Passat, Golf, Jetta and Leon platforms are wear items. City driving compresses the buffer thousands of times per year, and polyurethane ages with ozone exposure and temperature cycling. Workshops usually find the part due for replacement somewhere between 80,000 and 150,000 km, and always whenever front struts are renewed. Typical symptoms of a degraded 3C0412303C include:

• A hard knocking or clunking from the front axle over speed bumps, driveway edges or potholes.
• The front end bottoming out when the car is fully loaded, when towing, or when driven briskly over uneven roads.
• Visible crumbling, powder residue or permanent compression set once the dust cover is pulled back.
• A noticeably harsher ride, because the buffer no longer supplies its progressive cushioning stage.

Buffers are replaced in pairs per axle to keep the suspension response symmetric, and the dust covers should be inspected at the same time. Refitting new dampers behind a cracked buffer shortens the life of the new strut.

Polyurethane versus Rubber in Strut Bump Stop Production

Bonpora produces this reference in polyurethane, the same material class specified by the vehicle manufacturer for this component family. The table below summarises why polyurethane has become the standard for progressive stop buffers.

For buyers the practical meaning is simple: a polyurethane buffer keeps its height and damping curve for longer in service, reducing warranty claims on the surrounding strut assembly. More material background is available on our polyurethane bump stops page.

OEM Supply and Custom Strut Bump Stop Manufacturing at Bonpora

Beyond the standard catalogue programme, Bonpora operates as a custom suspension buffer manufacturer for brands that need their own specifications. Working from a drawing, a table or a physical sample, our engineers produce strut bump stops with custom core and outer diameters, heights from roughly 40 mm to 200 mm, and polyurethane densities tuned to the required compression curve. Tooling is developed in-house, which keeps sample lead times short and unit costs competitive at volume.

Typical custom projects include buffers for vehicles outside the VW Group range, heavy-duty versions for taxi and fleet programmes, and private-label production for suspension kit assemblers. Custom options extend to material hardness, colour, laser-marked part numbers and branded packaging, and our custom parts team supports the development from sample to serial production.

Ordering Information for Bonpora Nos 4110111

Bonpora Nos 4110111 (OE 3C0412303C) is produced with a standard lead time of 15 to 30 days and ships in neutral export packaging suitable for repacking under your own brand. The part carries a 1-year warranty, and MOQ is flexible for distributors testing the market or consolidating mixed-container orders. Contact our export team with the OE number and your destination market for a quotation, and we will respond with technical data and pricing within one working day.

FAQ

How do I confirm that the 3C0412303C fits my Passat, Golf or Leon?

Check the suspension specification rather than the body style. The catalogue assigns this 55 mm buffer to front axles without sport suspension on the Passat, without DCC on the Golf R and without the GLI package on the Jetta. Measuring the removed part is equally reliable: a height near 55 to 57 mm identifies this reference. You can also send your VIN to our sales team for verification before ordering.

Is the 3C0412303C a front or rear bump stop?

It is a front axle buffer, fitted left and right, two pieces per vehicle. The rear buffers on the related Passat and Jetta platforms carry separate references with 70 mm and 90 mm heights, so a front or rear mix-up is visible immediately from the height of the old part.

What is the difference between 3C0412303C and 1K0412303C?

Both are front axle buffers with a similar shape, but they differ in height and application. The 3C0412303C measures about 55 mm and serves Passat, Golf R, Jetta and Leon builds, while the 1K0412303C measures about 100 mm and serves standard front suspension on the Golf V and VI generation platforms. Ordering by height rather than by shape prevents the two from being interchanged.

Can Bonpora produce this buffer in a custom size or under my own brand?

Yes. We manufacture strut bump stops to customer drawings or samples, with heights from roughly 40 mm to 200 mm, adjustable polyurethane hardness, laser marking and private-label packaging. Send the drawing or the OE reference and your target quantity, and our engineering team will confirm feasibility and sample lead time.