--- product_id: 637972263 title: "Coolant Reservoir Water Expansion Tank for Audi S5 Sturdy No.8K0121405E | Coolant Radiator Reservoir Bottle with Sensor 1 Pcs" price: "454.10 DT" currency: TND in_stock: true reviews_count: 3 url: https://www.desertcart.tn/products/637972263-coolant-reservoir-water-expansion-tank-for-audi-s5-sturdy-no store_origin: TN region: Tunisia --- # Compact dimensions: 22x20.5x16.5 cm for seamless integration Heat-resistant durable polypropylene construction Precision custom fit for Audi S5 8T3 4.2 (2007-2012) Coolant Reservoir Water Expansion Tank for Audi S5 Sturdy No.8K0121405E | Coolant Radiator Reservoir Bottle with Sensor 1 Pcs **Price:** 454.10 DT **Availability:** ✅ In Stock ## Summary > 🚗 Keep Your Cool with Precision-Engineered Performance! ## Quick Answers - **What is this?** Coolant Reservoir Water Expansion Tank for Audi S5 Sturdy No.8K0121405E | Coolant Radiator Reservoir Bottle with Sensor 1 Pcs - **How much does it cost?** 454.10 DT with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.tn](https://www.desertcart.tn/products/637972263-coolant-reservoir-water-expansion-tank-for-audi-s5-sturdy-no) ## Best For - Customers looking for quality international products ## Why This Product - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Integrated Sensor Ready:** Comes equipped with a 2-pin sensor interface, enabling real-time coolant level monitoring for proactive vehicle care. - • **Compact Yet Robust Design:** Sized precisely to fit without compromise, this tank balances space efficiency with maximum coolant capacity. - • **Tailored for Your Audi S5:** Engineered for a perfect fit on 2007-2012 Audi S5 8T3 4.2 models, ensuring hassle-free installation and optimal performance. - • **Built to Endure Heat & Pressure:** Crafted from premium polypropylene, this reservoir withstands high temperatures, keeping your cooling system reliable under pressure. - • **Streamlined Installation Process:** Designed for quick replacement with clear step-by-step installation, minimizing downtime and getting you back on the road faster. ## Overview This Coolant Reservoir Water Expansion Tank is a durable, heat-resistant replacement part custom-designed for Audi S5 8T3 4.2 models (2007-2012). Made from high-quality polypropylene, it features a built-in 2-pin sensor for coolant monitoring and offers a precise fit for seamless installation, ensuring your vehicle’s cooling system runs smoothly and reliably. ## Description Buy TUCKBOLD Coolant Reservoir Water Expansion Tank for Audi S5 Sturdy No.8K0121405E | Coolant Radiator Reservoir Bottle with Sensor 1 Pcs: Reservoirs - desertcart.com ✓ FREE DELIVERY possible on eligible purchases Review: Great Fit - Excellent fitment and even comes with metal heat shield Review: Ruined my car - It broke itself in 4 months. Now I need a whole new cooling system….. do not buy!!!! ## Features - Custom Fit. Coolant Reservoir Water Expansion Tank suitable for Audi S5 8T3 4.2 2007-2012. - OE Number:8K0121405E; It's non-OEM part, but this Coolant Reservoir Water Expansion Tank is design for precise fitting for Audi S5 8T3 4.2 2007-2012 series and others. - Long Lasting Coolant Radiator Reservoir Tank. Made of fine PP that keeps it durable, reliable and functional accessories for running your vehicle smoothly - Installation. 1. Turn off and cool down the car, remove the bolts and the reservoir; 2. Allow the remaining coolant to flow back into the drain pan; 3. Replace the new reservoir tank and reinstall the coolant hose to the radiator and tighten the clamp; 4. Finally check if function well. - Heat Resistance Coolant Radiator Reservoir Bottle Info. Cap Includes: No, Sensor Includes: Yes, Pin Number: 2, Dimension: 22x20.5x16.5cm / 8.66"x8.07"x6.50"(L*W*H), 1 Pcs. ## Images ![Coolant Reservoir Water Expansion Tank for Audi S5 Sturdy No.8K0121405E | Coolant Radiator Reservoir Bottle with Sensor 1 Pcs - Image 1](https://m.media-amazon.com/images/I/51jzPsb0BCL.jpg) ![Coolant Reservoir Water Expansion Tank for Audi S5 Sturdy No.8K0121405E | Coolant Radiator Reservoir Bottle with Sensor 1 Pcs - Image 2](https://m.media-amazon.com/images/I/81ckPBaDp8L.jpg) ![Coolant Reservoir Water Expansion Tank for Audi S5 Sturdy No.8K0121405E | Coolant Radiator Reservoir Bottle with Sensor 1 Pcs - Image 3](https://m.media-amazon.com/images/I/71hZeANh2kL.jpg) ![Coolant Reservoir Water Expansion Tank for Audi S5 Sturdy No.8K0121405E | Coolant Radiator Reservoir Bottle with Sensor 1 Pcs - Image 4](https://m.media-amazon.com/images/I/71HfS7+tt8L.jpg) ![Coolant Reservoir Water Expansion Tank for Audi S5 Sturdy No.8K0121405E | Coolant Radiator Reservoir Bottle with Sensor 1 Pcs - Image 5](https://m.media-amazon.com/images/I/71S9j7dwFJL.jpg) ## Customer Reviews ### ⭐⭐⭐⭐⭐ Great Fit *by Z***Z on October 29, 2025* Excellent fitment and even comes with metal heat shield ### ⭐ Ruined my car *by D***Y on May 11, 2026* It broke itself in 4 months. Now I need a whole new cooling system….. do not buy!!!! ### ⭐⭐⭐⭐ Fits well but gave me other issues. *by D***D on October 4, 2024* Heat shield fell off prior to installation and after a few months of driving it is now leaking in a completely random spot. The fit was perfect but longevity is not there UPDATE: Vendor refunded my original purchase fully. I did buy another giving them the benefit of doubt. Will update if anything goes wrong. Just for other buyers it does not have the cap or rubber grommet on the bottom. Reuse your existing one. --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.tn/products/637972263-coolant-reservoir-water-expansion-tank-for-audi-s5-sturdy-no](https://www.desertcart.tn/products/637972263-coolant-reservoir-water-expansion-tank-for-audi-s5-sturdy-no) --- *Product available on Desertcart Tunisia* *Store origin: TN* *Last updated: 2026-09-20*