Genuine Audi A4 Coolant Reservoir Hose

Water Bypass Hose

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133 Coolant Reservoir Hoses found

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Audi A4 Water Pump Housing Part Number: 06L-121-111-P
$418.88 MSRP: $586.67
You Save: $167.79 (29%)
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Product Specifications
- Other Name: Thermostat; Thermostat Housing, Thermostat Unit
- Replaced by: 06L-121-111-N
- Replaces: 06L-121-111-M, 06L-121-111-L, 06L-121-111-F, 06L-121-111-H, 06L-121-111-J, 06L-121-111-G, 06L-121-111-K
- Warranty: This genuine part is guaranteed by Audi's factory warranty.
Fits the following Vehicles:
- 2017-2020 Audi A4 | Premium, Premium Plus, Prestige, Titanium | 4 Cyl 2.0 L GAS
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Audi A4 Expansion Tank Part Number: 8W0-121-405-L
$143.99 MSRP: $201.67
You Save: $57.68 (29%)
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Product Specifications
- Other Name: Tank; Reservoir
- Replaces: 8W0-121-405-G, 8W0-121-405-E, 8W0-121-405-F
- Warranty: This genuine part is guaranteed by Audi's factory warranty.
Fits the following Vehicles:
- 2017-2020 Audi A4 | Premium, Premium Plus, Prestige, Titanium | 4 Cyl 2.0 L GAS
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Audi A4 Hose & Tube Assembly Part Number: 06L-121-497-AA
$82.11 MSRP: $115.00
You Save: $32.89 (29%)
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Product Specifications
- Other Name: Pipe
- Replaces: 06L-121-497-J
- Warranty: This genuine part is guaranteed by Audi's factory warranty.
Fits the following Vehicles:
- 2017-2020 Audi A4 | Premium, Premium Plus, Prestige, Titanium | 4 Cyl 2.0 L GAS
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Audi A4 Overflow Hose Part Number: 8W0-121-081-BL
$8.96 MSRP: $14.00
You Save: $5.04 (36%)
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Product Specifications
- Other Name: Breather; Breather Tube
- Warranty: This genuine part is guaranteed by Audi's factory warranty.
Fits the following Vehicles:
- 2017-2018 Audi A4 | Premium, Premium Plus, Prestige | 4 Cyl 2.0 L GAS
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Audi A4 Reservoir Cap Part Number: 3B0-121-321
$23.24 MSRP: $37.18
You Save: $13.94 (38%)
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Product Specifications
- Other Name: Cover; Cap, Radiator Cap
- Warranty: This genuine part is guaranteed by Audi's factory warranty.
Fits the following Vehicles:
- 2005-2016, 1998-2001 Audi A4 | Avant, Base, Cabriolet, Premium, Premium Plus, Prestige | 4 Cyl 1.8 L GAS, 4 Cyl 2.0 L GAS, 6 Cyl 2.8 L GAS, 6 Cyl 3.2 L GAS
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Audi A4 Expansion Tank Part Number: 8K0-121-403-AC
$73.78 MSRP: $103.34
You Save: $29.56 (29%)
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Product Specifications
- Other Name: Tank; Reservoir
- Replaces: 8K0-121-403-H, 8K0-121-403-T, 8K0-121-403-Q, 8K0-121-403-D, 8K0-121-403-G
- Warranty: This genuine part is guaranteed by Audi's factory warranty.
Fits the following Vehicles:
- 2009-2016 Audi A4 | Base, Premium, Premium Plus, Prestige | 4 Cyl 2.0 L GAS
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Audi A4 Overflow Hose Part Number: 8K0-121-081-BF
$27.61 MSRP: $44.18
You Save: $16.57 (38%)
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Product Specifications
- Other Name: Venthose
- Warranty: This genuine part is guaranteed by Audi's factory warranty.
Fits the following Vehicles:
- 2013-2016 Audi A4 | Base, Premium, Premium Plus, Prestige | 4 Cyl 2.0 L GAS
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Audi A4 Hose & Tube Assembly Part Number: 06D-121-492-J
$122.57 MSRP: $171.66
You Save: $49.09 (29%)
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Product Specifications
- Other Name: Pipe; Coolant Line, Pipe Assembly
- Replaces: 06D-121-492-H, 06D-121-492-F
- Warranty: This genuine part is guaranteed by Audi's factory warranty.
Fits the following Vehicles:
- 2005-2009 Audi A4 | Base, Cabriolet | 4 Cyl 1.8 L GAS, 4 Cyl 2.0 L GAS
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Audi A4 Water Inlet Pipe Part Number: 06L-121-492-R
$127.33 MSRP: $178.33
You Save: $51.00 (29%)
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Product Specifications
- Other Name: Pipe
- Replaces: 06L-121-492-J
- Warranty: This genuine part is guaranteed by Audi's factory warranty.
Fits the following Vehicles:
- 2017-2020 Audi A4 | Premium, Premium Plus, Prestige, Titanium | 4 Cyl 2.0 L GAS
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Audi A4 Expansion Tank Part Number: 8W0-121-405-K
$55.66 MSRP: $76.67
You Save: $21.01 (28%)
Ships in 1-2 Business Days
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Product Specifications
- Other Name: Tank; Reservoir
- Warranty: This genuine part is guaranteed by Audi's factory warranty.
Fits the following Vehicles:
- 2020 Audi A4 | Premium, Premium Plus, Prestige | 4 Cyl 2.0 L GAS
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Audi A4 Water Outlet Part Number: 06K-121-132
$22.74 MSRP: $36.38
You Save: $13.64 (38%)
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Product Specifications
- Other Name: Flange
- Warranty: This genuine part is guaranteed by Audi's factory warranty.
Fits the following Vehicles:
- 2017-2020 Audi A4 | Premium, Premium Plus, Prestige, Titanium | 4 Cyl 2.0 L GAS
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Audi A4 Hose & Tube Assembly Part Number: 078-121-597-K
$0.01
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Product Specifications
- Other Name: Pipe; Coolant Line, Inlet Pipe
- Position: Driver Side
- Warranty: This genuine part is guaranteed by Audi's factory warranty.
Fits the following Vehicles:
- 2000-2001 Audi A4 | Base | 6 Cyl 2.8 L GAS
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Audi A4 Overflow Hose Part Number: 8W0-121-081-ED
$22.74 MSRP: $36.38
You Save: $13.64 (38%)
Ships in 1-2 Business Days
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Product Specifications
- Other Name: Breather; Breather Tube, Vent Tube
- Replaces: 8W0-121-081-DR
- Warranty: This genuine part is guaranteed by Audi's factory warranty.
Fits the following Vehicles:
- 2018-2020 Audi A4 | Premium, Premium Plus, Prestige, Titanium | 4 Cyl 2.0 L GAS
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Audi A4 Auxiliary Radiator Grommet Part Number: 7P0-121-276
$5.90 MSRP: $9.23
You Save: $3.33 (37%)
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Product Specifications
- Other Name: Grommet
- Warranty: This genuine part is guaranteed by Audi's factory warranty.
Fits the following Vehicles:
- 2017-2020 Audi A4 | Premium, Premium Plus, Prestige, Titanium | 4 Cyl 2.0 L GAS
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Audi A4 Upper Hose Part Number: 8E0-121-101-R
$71.39 MSRP: $99.99
You Save: $28.60 (29%)
Ships in 1-2 Business Days
Product Specifications
- Other Name: Water Hose
- Position: Upper
- Warranty: This genuine part is guaranteed by Audi's factory warranty.
Fits the following Vehicles:
- 2005-2009 Audi A4 | Base, Cabriolet | 4 Cyl 1.8 L GAS, 4 Cyl 2.0 L GAS
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Audi A4 Thermostat Switch Housing Part Number: 893-906-231
$10.25 MSRP: $13.36
You Save: $3.11 (24%)
Ships in 1-2 Business Days
Product Specifications
- Other Name: Housing; Resistor
- Warranty: This genuine part is guaranteed by Audi's factory warranty.
Fits the following Vehicles:
- 1996-2001 Audi A4 | Avant, Base | 4 Cyl 1.8 L GAS, 6 Cyl 2.8 L GAS
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Audi A4 Water Pipe Part Number: 078-121-081-J
Product Specifications
- Other Name: Pipe; Front Pipe
- Replaces: 078-121-081-D, 078-121-081-B
- Warranty: This genuine part is guaranteed by Audi's factory warranty.
Fits the following Vehicles:
- 1996-2001 Audi A4 | Avant, Base | 6 Cyl 2.8 L GAS
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Audi A4 Thermostat Housing Part Number: 06B-121-111-K
$264.76 MSRP: $370.82
You Save: $106.06 (29%)
Ships in 1-2 Business Days
Product Specifications
- Other Name: Thermostat
- Replaces: 06B-121-111-G, 06B-121-111-D, 06B-121-111-H
- Warranty: This genuine part is guaranteed by Audi's factory warranty.
Fits the following Vehicles:
- 2002-2006 Audi A4 | Base, Cabriolet | 4 Cyl 1.8 L GAS, 4 Cyl 2.0 L GAS
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Audi A4 Radiator Upper Insulator Part Number: 8D0-121-276-B
$12.50 MSRP: $20.00
You Save: $7.50 (38%)
Ships in 1-2 Business Days
Product Specifications
- Other Name: Mounting; Radiator Insulator, Radiator Upper Mount
- Position: Upper
- Warranty: This genuine part is guaranteed by Audi's factory warranty.
Fits the following Vehicles:
- 2000-2001 Audi A4 | Base | 6 Cyl 2.8 L GAS
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Audi A4 Connector Hose Part Number: 078-121-096-AF
$13.75 MSRP: $22.00
You Save: $8.25 (38%)
Ships in 1-2 Business Days
Product Specifications
- Other Name: Hose
- Warranty: This genuine part is guaranteed by Audi's factory warranty.
Fits the following Vehicles:
- 2000-2001 Audi A4 | Base | 6 Cyl 2.8 L GAS

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1-20 of 133 Results

Audi A4 Coolant Reservoir Hose

The Audi A4 Coolant Reservoir Hose maintains engine temperature equilibrium by transferring excess coolant between the overflow tank and the radiator while preventing the entry of damaging air pockets. Designed from heat resistant rubber, it is capable of withstanding constant thermal cycling. Audi drivers can rely on it to keep pressure stable and heating worries at bay. The hose keeps things balanced, improving cooling efficiency by returning expanding coolant to the radiator when conditions get too hot and pulling it into the tank when things cool down. The continuous air flow protects against damaging air, keeps vital Audi alloys clean and preserves the car's reputation for lively performance. One of two choices is appropriate for the Audi lineup, a moulded factory routed piece or a flexible silicone path, which is cut to the exact length, diameter and connectors specified for each individual A4, ensuring the flow is unimpeded regardless of whether the car is front drive or quattro. Whether your A4 is a sedan or a wagon, the fit is precise so that installation is quick and confidence is maximized. By conducting simple checks for cracks, soft areas and residue, vehicle owners can easily change the Coolant Reservoir Hose before a drip develops into an overheat, thus enhancing safety on daily commutes. The characteristics of the Coolant Reservoir Hose provide advantages with rapid heat exchange and stable gauge readings. Its thick walls resist swelling, OEM style clips lock tight and the smooth bore reduces turbulence. Frequent inspection of the Coolant Reservoir Hose goes a long way in avoiding any sweet smells and puddles that are indicative of trouble, allowing Audi core performance to last mile after mile.

Choose original equipment manufacturer Coolant Reservoir Hose for great performance and strong durability. They use Audi's official craftsmanship and high-grade materials, and meet strict quality standards. Are you looking for quality Coolant Reservoir Hose at a good price? Come to our online store. We carry a wide range of genuine parts for your Audi A4 and the prices are competitive. Each part comes with the manufacturer's warranty. You can install with confidence and get steady results. Over time, you'll save money and avoid hassle. Keep your maintenance simple and protect your vehicle with OEM parts. Get the quality your A4 needs now.