Strut Bump Stop 5033.26: Polyurethane Front Suspension Buffer for Citroen and Peugeot Models

Bump stop 5033.26 is the original-equipment front suspension buffer specified by PSA for a wide family of Citroen and Peugeot models produced from the mid 1980s through the early 2010s, among them the Citroen AX, Saxo, ZX and Xsara as well as the Peugeot 205, 106, 306 and 405. Bonpora manufactures this part under number 4110237 in polyurethane, molded to the original geometry of 19 mm bore, 53.5 mm outer diameter and 79 mm height. This guide summarizes where the part fits, which aftermarket references it replaces, how buyers should search for it, and what to verify when ordering replacement or custom bump stops from a factory in China.

What Does the 5033.26 Bump Stop Do?

A bump stop, also called a suspension buffer or jounce bumper, is the elastomer element mounted on the piston rod of each front strut. It stays out of the working range during normal driving and comes into play only when the suspension reaches full compression, for example over deep potholes, speed bumps or when the vehicle is heavily loaded. At that moment the buffer absorbs the final part of the travel and prevents metal-to-metal contact between the strut body, the spring seat and the vehicle structure.

On the compact PSA platforms where 5033.26 is used, the front strut is short and the clearance to the bump stop is limited, so the condition of this small part has a visible effect on how the car behaves at full compression. A healthy buffer keeps the impact progressive and quiet, while a cracked or collapsed one passes the shock straight into the body.

Position in the Front Strut Assembly

The 5033.26 buffer slides over the damper rod inside the protective boot, between the top mount and the damper body. It works together with the strut mount and the dust cover, and it is common practice to renew all three items at the same time. Catalogues such as SKF and Monroe list 5033.26 within complete protection kits that combine the boot and the buffer, which reflects how installers actually order the job: one part number covers the buffer, the boot and the fixing clips for one side of the axle.

Symptoms of a Worn or Missing Buffer

• Hard knocking or thudding from the front axle over sharp bumps, caused by the strut reaching the end of its travel without damping.
• Visible cracking, powdering or permanent compression of the old buffer once the strut is disassembled.
• Uneven tire wear and unsettled steering after the suspension has been bottoming out repeatedly.
• Damage to the dust cover itself, which then lets dirt reach the damper rod seal and shortens the life of the shock absorber.

Because the buffer cannot be inspected without partial disassembly, most workshops replace it preventively whenever struts or boots are renewed.

Vehicle Fitment: Which Citroen and Peugeot Models Use 5033.26

Catalogue data for 5033.26 covers a long list of front-wheel-drive PSA models with MacPherson front struts. The table below lists the applications most frequently quoted by distributors.

Front Axle Only, Two Pieces per Vehicle

5033.26 is catalogued for the front axle on both sides, so a complete vehicle requires two pieces, and several suppliers note that the buffers should be replaced in pairs to keep compression behavior symmetrical between the left and right struts. The rear axles of these models use different part numbers, so distributors should not substitute 5033.26 into rear applications even where the dimensions look close.

Extended Catalogue Listings Beyond PSA

Some European catalogues extend the application list of the same geometry to the Fiat Tipo and Tempra and to certain Suzuki Vitara variants. These extended listings usually come from protection-kit cross references rather than from the PSA OE drawing, so the practical rule for buyers is simple: confirm fitment by the dimensions and by the cross reference number, and treat non-PSA listings as secondary until they are verified against the actual strut on the vehicle.

Technical Specifications of the Bonpora 4110237

The catalogue height of 79 mm and the weight of roughly 50 grams per piece match the data published by the main European aftermarket brands for this reference, which makes first-article inspection straightforward for importers who receive samples.

Aftermarket Cross References for 5033.26

Because the PSA OE reference has been in catalogues for decades, nearly every major European brand lists an equivalent. The following cross references are the ones distributors request most often.

Searching 5033.26 Versus 503326

The PSA reference is normally printed with a dot, as 5033.26, but many databases store it without punctuation as 503326. Search engines treat these as different strings, so a buyer who finds nothing under one form should immediately repeat the query under the other. Adding the brand and model, for example 503326 Citroen ZX front bump stop, or the leading aftermarket number Febi 19617, usually narrows the results to suppliers who actually stock the part.

Why Polyurethane Is the Standard Material Here

The original buffers were produced in rubber, and most current aftermarket versions, including the Bonpora 4110237, are molded in polyurethane. For a part that spends years compressed near the top of its travel, the material choice decides how long the buffer keeps its nominal height and damping behavior.

Compression Set and Height Retention

Polyurethane shows a lower permanent compression set than conventional rubber, which means the buffer is less likely to collapse to a shorter free height after long service. A collapsed buffer effectively removes the last stage of suspension travel, and the driver only notices when the strut begins to knock.

Resistance to Ozone, Temperature and Aging

The front wheel arch is an aggressive environment: ozone attack, road salt, oil mist and repeated flexing all work against an elastomer part. Polyurethane formulations resist ozone cracking and maintain their properties across a wide temperature span, which is why the material has become the default for this product family. Bonpora also supplies a wider range of molded polyurethane bump stops for European, Japanese and Korean applications.

Replacement Guidance for Workshops and Distributors

Replace in Pairs and Inspect the Boot

Workshops replacing 5033.26 should fit two new buffers per axle and inspect the dust covers at the same time. A split boot allows water and grit to reach the damper rod, and the resulting seal damage will cost the customer a full strut far sooner than the price of a boot. Pairing the buffer with a new dust cover kit is the most economical way to complete the repair in one visit.

What Distributors Should Check on Arrival

• Height, bore and outer diameter measured against the 19 by 53.5 by 79 mm specification.
• Surface quality: no cracks, flash or bonding defects around the bore.
• Material identification: polyurethane should feel firm yet elastic, not sticky like degraded rubber.
• Packaging integrity for export cartons, since the part is light but can be deformed by stacking pressure.

Ordering 5033.26 Bump Stops from Bonpora

Bonpora produces the 4110237 in batch quantities for wholesale distribution, with neutral export packaging as standard so distributors can ship under their own brand. Standard delivery time is 15 to 30 days depending on order volume, and every order is covered by a 1 year warranty against material and manufacturing defects.

OEM and Custom Design Support

For buyers who need a different height, bore or hardness for a specific platform, the engineering team supports OEM drawings and sample-based development, from tooling to first-article reports. Details of the custom parts service include drawing review, material selection and small trial batches before serial production.

Frequently Asked Questions

Which cars does bump stop 5033.26 fit?

It fits the front suspension of a wide range of Citroen and Peugeot models, including the Citroen AX, Saxo, ZX, Xsara, Berlingo and C15, and the Peugeot 104, 205, 106, 206, 305, 306, 309, 405 and Partner. Catalogue production years span roughly 1983 to 2012 depending on the model, and the position is the front axle on both sides.

What are the dimensions of the 5033.26 buffer?

The reference dimensions are a 19 mm inner bore, a 53.5 mm outer diameter and a 79 mm height, with a weight of about 50 grams per piece. These values match the catalogue data published for the equivalent Febi 19617 and Meyle 11-146420001 references.

Is 5033.26 the same part as 503326?

Yes. The dot is part of the PSA formatting convention, and most databases and invoices list the same reference as 503326. Both forms identify the same front axle buffer, and the same applies to the equivalent aftermarket numbers from Febi, SWAG, Meyle, MAPCO and other brands.

Can Bonpora supply the buffer with a dust cover or in custom packaging?

Yes. Bonpora can quote the buffer alone or combined with dust cover kits for the same applications, and supports neutral export packaging as standard along with private-label packaging and OEM part numbers on request, subject to order quantity.

Request a Quote for Bump Stop 5033.26

Distributors, importers and workshop chains can request a quotation for the 5033.26 front bump stop under Bonpora number 4110237 by sending the required quantity and destination port. Sample quantities for first-article inspection, technical drawings in PDF, and cross-reference lists for the full polyurethane bump stop program are available on request, with standard lead time of 15 to 30 days from confirmed order.