Radiator – 8E0 121 251 AQ
Radiator for the Audi A4 (B6/B7) platform, OE number 8E0 121 251 AQ. Main group 121 sub-group 251 identifies this as a radiator. Revision index AQ. 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 | 8E0 121 251 AQ |
| SKU | AUD-8E0121251AQ |
| 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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Return unused parts within 30 days for a full refund.
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Customer reviews
Verified feedback from Audi owners and independent workshops.
4.6
7 reviews
Sofia Ellery
January 31, 2026
Perfect fit, no modification (A8 D4)
Replacement for my 2013 A8 D4 3.0 TFSI V6. The plastic feels substantial rather than the brittle stuff that cracks at the neck. I bled it through the proper procedure and it has held level ever since. Result is the gauge sits dead centre now even in traffic on a hot day. Exactly what I needed.
Amara Ferreira
December 1, 2025
Perfect fit, no modification
My A6 C6 needed this doing at 169k miles. I flushed the system properly and refilled with the correct G13 before bleeding. The plastic feels substantial rather than the brittle stuff that cracks at the neck. Result is the gauge sits dead centre now even in traffic on a hot day. Good value against the dealer price.
Amara Almeida
October 29, 2025
Straight swap
My A6 C8 needed this doing at 162k miles. I pressure tested it to 1.4 bar before fitting and it held without a drop. 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. No complaints at all.
Tobias Castellanos
September 26, 2025
Better core than the original
Cross-referenced the OE number against my 2016 A3 8V 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 no more creeping temperature when towing. Would order again without hesitation.
Nora Silva
April 24, 2025
Temps back to normal
Replacement for my 2012 A4 B8.5 3.0 TFSI V6. I pressure tested it to 1.4 bar before fitting and it held without a drop. Front end off, old one out, this one in over a long Saturday. Result is the coolant level has not moved in four months. Exactly what I needed.
Tobias Krause
April 17, 2025
Holds pressure beautifully
My Q8 4M needed this doing at 151k miles. The plastic feels substantial rather than the brittle stuff that cracks at the neck. Front end off, old one out, this one in over a long Saturday. Result is the gauge sits dead centre now even in traffic on a hot day.
Laura Adeyemi
April 3, 2025
Solved my overheating
Went on my A4 B8.5 2.0 TFSI at 130k miles. I bled it through the proper procedure and it has held level ever since. The plastic feels substantial rather than the brittle stuff that cracks at the neck. Result is no more creeping temperature when towing.