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Details
| Specification | Value |
|---|---|
| Brand | NRF |
| Category | Radiator |
| Core Length [mm] | 632 mm |
| Core Width [mm] | 398 mm |
| Core Depth [mm] | 32 mm |
OE/OEM numbers (4)
Search by this OE number to find compatible parts
- AUDI / SKODA / VW—4B0121251F
- AUDI / SKODA / VW—4B0121251K
- AUDI / SKODA / VW—8D0121251D
- AUDI / SKODA / VW—8D0121251N
Where this part fits
Original-fit position for OE 4B0121251K. The red ring marks where this part installs on the vehicle.
About this product
Sourced from NRF, this radiator (539504) combines precision engineering with durable materials to meet the demands of everyday driving and extended service intervals. Technical specifications — Material: Steel, Supplementary Article/Info 2: 396, Radiator type: Steel, Core Length [mm]: 632 mm, Core Width [mm]: 398 mm — are verified against the OEM data sheet to guarantee fitment accuracy and performance parity with the original equipment. Verified to fit AUDI, SKODA, VW models. All compatibility data is cross-checked against the TecDoc database — select your vehicle to confirm the part matches your specific engine and year. This part supersedes original equipment references: 01103117, 01103120, 03002110, 03002124 and 28 more. Matching these numbers confirms a like-for-like replacement with no loss of function. NRF is a recognised supplier of automotive replacement components to independent workshops and dealer networks across Europe. All parts are sourced from authorised distribution channels and carry full manufacturer traceability — you receive exactly the same component supplied to professional garages and dealer workshops. If fitment or specifications do not match your vehicle, our technical team can help identify the correct alternative — use the vehicle selector or contact us with your VIN for a guaranteed-fit recommendation. Replacing worn components on schedule preserves your vehicle's safety, reliability, and resale value — and aftermarket parts from established brands deliver OEM-equivalent performance at a fraction of the dealer price. Every part is dispatched from our UK warehouse with a 30-day money-back guarantee and free hassle-free returns.
Radiator buying guide
Why replace this part?
The radiator dissipates engine heat by transferring it from coolant to the air. A leaking or clogged radiator causes engine overheating, which can result in catastrophic engine damage including warped heads and blown gaskets.
Signs you need a replacement
- Coolant leaks or puddles under the car
- engine overheating
- discoloured or rusty coolant
- visible corrosion or damage to radiator fins
- steam from under the bonnet
When to replace
Typically lasts 8–10 years. Replace when leaks develop or internal blockages cause overheating. Flush cooling system every 5 years.
About NRF
NRF, founded in 1927 in the Netherlands, is Europe's leading specialist manufacturer of cooling and climate control components. NRF specialises in radiators, condensers, evaporators, compressors, heater cores, and cooling fans. As an OE supplier to major manufacturers and with products tested to exceed factory specifications, NRF ensures reliable thermal management for all vehicle types. With nearly a century of cooling expertise and the largest product range in the sector, NRF is the first choice for heating, cooling, and air conditioning repairs.
Suitable cars
Equivalent products (28)
Show all 28 OE numbers
Radiator NRF 539504 — compatible car models
| Car models | AUDI: A4 B5 (8D2), A4 B5 Avant (8D5), A6 C4 (4A2), A6 C4 Avant (4A5), A6 C5 (4B2, 4B4), A6 C5 Avant (4B5, 4B6), ALLROAD C5 (4BH); SKODA: SUPERB I (3U4); VW: PASSAT B5 (3B2), PASSAT B5.5 (3B3), PASSAT B5.5 Variant (3B6), PASSAT B5 Variant (3B5) |
|---|---|
| Engines | 2.4; 2.8; 2.7 T quattro; 2.5 TDI |
| Year of manufacture | 1994-2008 |
| Manufacturer article number (MPN) | 539504 |
| OE part numbers | 4B0121251F, 4B0121251K, 8D0121251D, 8D0121251N |
Compatibility check
Loading vehicle data…
Please wait while we load vehicle compatibility information.Description and what's included
NRF 539504 EASY FIT. Core Depth [mm]: 32 mm. Core Length [mm]: 632 mm. Core Width [mm]: 398 mm. Material: 1. Radiator type: 1. Supplementary Article/Info 2: 396
- 1x Radiator
Shipping, returns, warranty
Free UK delivery on orders over £99.00. Express and standard shipping available.
- Standard delivery: 2-5 business days
- Express delivery: 1-2 business days
- Free returns within 14 days
- All parts backed by manufacturer warranty
Warranty: 12-month manufacturer warranty on all parts. 14-day money-back guarantee if the part doesn't fit your vehicle.
Frequently Asked Questions
Is this Radiator compatible with my car?
This Radiator fits AUDI, SKODA, VW vehicles. Use the vehicle selector at the top of the page to check exact compatibility — enter your car's make, model, and engine for a confirmed fitment match. All fitment data is verified through TecDoc.
What specifications does this NRF Radiator have?
This NRF Radiator has the following specifications: Material: 1; Supplementary Article/Info 2: 396; Radiator type: 1; Core Length [mm]: 632 mm; Core Width [mm]: 398 mm; Core Depth [mm]: 32 mm. Check the full specifications table above for complete details.
What OE part numbers does this Radiator replace?
This Radiator replaces OE part numbers: 4B0121251F, 4B0121251K, 8D0121251D, 8D0121251N. Cross-reference these numbers with your vehicle's original part number to confirm compatibility.
How much does a Radiator cost?
This NRF Radiator is available for £91.99. Radiator prices vary depending on brand, specifications, and vehicle compatibility. NRF parts offer a balance of quality and value, backed by our 14-day money-back guarantee.
How do I know when to replace my Radiator?
Signs of a failing radiator include visible coolant leaks (coloured fluid under the vehicle), engine overheating, coolant level dropping without explanation, or discolouration and corrosion on the radiator fins.
What tools do I need to replace a Radiator?
Tools needed: coolant drain pan, hose clamp pliers, flat-head screwdriver, 8-10mm socket, new coolant (correct type and mix ratio), funnel. Difficulty: Moderate DIY. Safety warning: Never open the radiator cap or coolant expansion tank on a hot engine -- pressurised coolant causes severe burns. Dispose of old antifreeze responsibly as it is toxic to animals.
Can I use this part as a replacement for OE 4B0121251F?
Yes, this NRF Radiator is a direct replacement for OE part number 4B0121251F. It is manufactured to meet or exceed original equipment specifications, ensuring proper fitment and performance. All cross-reference data is verified through TecDoc.
Related categories
Common OE numbers for this part
Common original equipment numbers linked to stocked alternatives.
