Radiator – 4F0 121 251 AF
Radiator for the Audi A6 (C6) platform, OE number 4F0 121 251 AF. Main group 121 sub-group 251 identifies this as a radiator. Revision index AF. Cooling capacity and mounting differ between engine variants on the same platform — confirm against your engine code before ordering.
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Technical specifications
| Part Number | 4F0 121 251 AF |
| SKU | AUD-4F0121251AF |
| Brand | |
| Category | Radiators |
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3–5 business days. Free on orders over $150.
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Order before 2 PM for next business day delivery.
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Customer reviews
Verified feedback from Audi owners and independent workshops.
4.3
4 reviews
Ingrid Duarte
August 13, 2026
Solved my overheating
Fitted to my 2008 A4 B8. The plastic feels substantial rather than the brittle stuff that cracks at the neck. I flushed the system properly and refilled with the correct G13 before bleeding. Result is no more creeping temperature when towing. Will be back for the other side.
Freya Lindqvist
July 23, 2026
Straight swap
Fitted to my 2014 A3 8V. The plastic feels substantial rather than the brittle stuff that cracks at the neck. All the mounting points and hose stubs lined up without any persuasion. Result is intake temps dropped noticeably on a long motorway pull.
Marcus Ellery
March 1, 2026
Temps back to normal
My RS4 B7 needed this doing at 42k miles. I bled it through the proper procedure and it has held level ever since. The end tanks are properly crimped with clean seams all the way round. Result is no more creeping temperature when towing. No complaints at all.
Yara Mensah
August 12, 2025
Perfect fit, no modification
Cross-referenced the OE number against my 2012 Q3 8U before ordering. The end tanks are properly crimped with clean seams all the way round. I bled it through the proper procedure and it has held level ever since. Result is the coolant level has not moved in four months. Exactly what I needed.