26 Drivetrain parts are listed for the 2021 Audi A4, in 7 part types, covering both the 2.0L L4 ELECTRIC/GAS Turbocharged and the 2.0L L4 Turbocharged. Each one has a brand, a manufacturer part number and notes that say where it fits.
The drivetrain system on the 2021 Audi A4 moves power from transmission to wheels through axles, CV joints, driveshafts, differentials and wheel-end hardware. The largest groups are CV Axle (7 parts), CV Joint Boot (6 parts) and Drive Shaft (5 parts). The other 4 part types cover the remaining 8 parts.
The 2021 Audi A4 was sold with both the 2.0L L4 ELECTRIC/GAS Turbocharged and the 2.0L L4 Turbocharged. Every part on this page is engine-specific. Each part shows which engine(s) it fits.
The most listed brands for 2021 Audi A4 drivetrain parts are GKN (8 parts), VAICO (6 parts) and TIMKEN (2 parts), plus 8 more brands. Quality grades include Standard Replacement and Premium.
3 parts on this 2021 Audi A4 page carry a "Popular" badge — the source catalog's flag for options frequently chosen for this vehicle — including TOP NOTCH TN19007PR (CV Axle) and GKN 306619 (CV Joint Boot). Click any part number to see every vehicle that part fits.
Axle Shaft Seal
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| TIMKEN Fits: 2.0L L4 Turbocharged | SL260526 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | Rear LeftA4 Quattro | View on Amazon |
| TIMKEN Fits: 2.0L L4 Turbocharged | SL260529 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | Rear RightA4 Quattro | View on Amazon |
This table covers the seals where an axle shaft exits the housing. Typical signs include a wet housing, a drip after sitting, or fluid flung off a rotating shaft. Fix the surface the seal rides on. A new seal on a grooved shaft will leak again.
2 Axle Shaft Seal parts for the 2021 Audi A4 come from TIMKEN.
Listed part numbers: TIMKEN SL260526 and TIMKEN SL260529.
CV Axle
Premium
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| TOP NOTCH Popular Fits: 2.0L L4 Turbocharged | TN19007PR | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | Performance | View on Amazon |
| GSP Fits: 2.0L L4 Turbocharged | PR23011 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | Performance Revolution | View on Amazon |
Standard Replacement
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| APWI Fits: 2.0L L4 Turbocharged | AD8352 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | FrontA4 Quattro | View on Amazon |
| GKN Fits: 2.0L L4 Turbocharged | GKND12163 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | Outboard Joint Type: Fix Ball Joint GKN SX | View on Amazon |
| GSP Fits: 2.0L L4 Turbocharged | NCV23011 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | FrontA4 Quattro | View on Amazon |
| TOP NOTCH Fits: 2.0L L4 Turbocharged | TN19007 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | FrontA4 Quattro | View on Amazon |
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| GKN Fits: 2.0L L4 Turbocharged | GKND12939 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | Outboard Joint Type: Fix Ball Joint SX | View on Amazon |
This table covers the complete CV axle shafts from differential (or hub) to wheel. Typical signs include a click in tight turns, grease flung around the wheel well, or a vibration that builds with speed. A torn boot caught early is a boot kit; caught late it is the whole axle. Torque the axle nut to the method in the notes.
7 CV Axle parts for the 2021 Audi A4 come from 4 brands — TOP NOTCH, GSP, GKN and 1 other brand. The "Popular" part is TOP NOTCH TN19007PR.
In the Premium grade, TOP NOTCH and GSP supply 2 parts: a step above OE specification in materials, tolerances or warranty terms. A representative part number is TOP NOTCH TN19007PR.
In the Standard Replacement grade, APWI, GKN, GSP and 1 other brand supply 4 parts: built to original-equipment specification. A representative part number is APWI AD8352.
1 further part sits outside the graded sections, with the same engine-level match.
Listed part numbers: TOP NOTCH TN19007PR, GSP PR23011 and APWI AD8352, plus the other parts above.
CV Joint
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| GKN Fits: 2.0L L4 Turbocharged | 306280 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | Thermosplastic Elastomer (TPE) | View on Amazon |
| VAICO Fits: 2.0L L4 Turbocharged | V107738 | 🇺🇸 US | Front Inner | View on Amazon |
This table covers the constant-velocity joints at each end of a drive axle.
2 CV Joint parts for the 2021 Audi A4 come from 2 brands — GKN and VAICO.
Part numbers include GKN 306280 and VAICO V107738.
CV Joint Boot
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| GKN Popular Fits: 2.0L L4 Turbocharged | 306619 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | Thermoplastic ElastomerThermosplastic Elastomer (TPE) | View on Amazon |
| BECK/ARNLEY Fits: 2.0L L4 Turbocharged | 1032892 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | Front OuterA4 Quattro | View on Amazon |
| GKN Fits: 2.0L L4 Turbocharged | 306313 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | OUTER Diameter 1.023 InThermoplastic Elastomer | View on Amazon |
| GKN Fits: 2.0L L4 Turbocharged | 306188 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | OUTER Diameter 1.063 InThermoplastic Elastomer | View on Amazon |
| REIN Fits: 2.0L L4 Turbocharged | BKN0109 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | Front OuterA4 Quattro | View on Amazon |
| VAICO Fits: 2.0L L4 Turbocharged | V105635 | 🇺🇸 US | Front OuterGrade: AM | View on Amazon |
This table covers the boots that keep grease in a CV joint. Typical signs include a split boot, grease flung around the joint, or a click once grit is inside. A boot caught early is a kit. Once the joint has clicked, the joint itself is usually worn.
6 CV Joint Boot parts for the 2021 Audi A4 come from 4 brands — GKN, BECK/ARNLEY, REIN and 1 other brand. The "Popular" part is GKN 306619.
Part numbers include GKN 306619, BECK/ARNLEY 1032892 and GKN 306313, among others listed above.
Differential Seal
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| ELRING Fits: 2.0L L4 Turbocharged | 852060 | 🇨🇦 CA | Height [MM]: 7Radial Shaft Seal Design: AS2W | View on Amazon |
This table covers the seals at the Differential. Typical signs include a wet housing, a drip after sitting, or fluid flung off a rotating shaft. Fix the surface the seal rides on. A new seal on a grooved shaft will leak again.
One part is listed for the 2021 Audi A4 — ELRING 852060.
Drive Shaft
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| GKN Popular Fits: 2.0L L4 Turbocharged | GKNP20085 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | RearAWD | View on Amazon |
| DORMAN Fits: 2.0L L4 Turbocharged | 986581 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | Length: 65.75" | View on Amazon |
| GKN Fits: 2.0L L4 Turbocharged | GKNP20091 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | RearAWD | View on Amazon |
| VAICO Fits: 2.0L L4 Turbocharged | V107729 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | Fits A4 QuattroLength: 463 | View on Amazon |
| WJB / INMOTION PARTS Fits: 2.0L L4 Turbocharged | WDS86581 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | RearAWD | View on Amazon |
This table covers the driveshafts that carry torque from the transmission or transfer case.
5 Drive Shaft parts are listed for the 2021 Audi A4, from GKN, DORMAN, VAICO and 1 other brand. GKN GKNP20085 carries the "Popular" badge.
Listed part numbers: GKN GKNP20085, DORMAN 986581 and GKN GKNP20091, plus the other parts above.
Transfer Case Fluid
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| VAICO Fits: 2.0L L4 Turbocharged | V600430 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | Transfer Case Oil DTF-1 L | View on Amazon |
| VAICO Fits: 2.0L L4 Turbocharged | V600431 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | Grade: AMTransfer Case Fluid, DTF-1 - 5 Liter | View on Amazon |
| VAICO Fits: 2.0L L4 Turbocharged | V600432 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | Grade: OEMTransfer Case Oil DTF-1-20 L | View on Amazon |
This table covers the fluids specified for the transfer case. Typical signs include discolored fluid, a burnt smell, or a level that keeps dropping. Use only the specification in the notes — the tables group grades because they are not interchangeable.
3 Transfer Case Fluid parts for the 2021 Audi A4 come from VAICO.
This group includes VAICO V600430, VAICO V600431 and VAICO V600432.
Buying Drivetrain Parts for a 2021 Audi A4
On this vehicle, the drivetrain system moves power from transmission to wheels through axles, CV joints, driveshafts, differentials and wheel-end hardware.
- Match the engine first. Every drivetrain part here is engine-specific; each row shows which engine(s) it fits.
- Read the notes on each row for position, trim and spec qualifiers before you order.
- Where labor overlaps, replace the differential or transfer-case fluid with any axle or seal job while everything is already open.
- Cross-reference the manufacturer part number against your old part or a service-manual listing.
Start with the largest groups on this page: CV Axle and CV Joint Boot .
Frequently Asked Questions
How many drivetrain parts fit the 2021 Audi A4?
Our catalog currently lists 26 drivetrain parts for the 2021 Audi A4 across 7 subcategories and 11 brands, covering both the 2.0L L4 ELECTRIC/GAS Turbocharged and the 2.0L L4 Turbocharged. Each part is matched to the engine(s) it fits.
Do drivetrain parts differ between 2021 Audi A4 engines?
Yes. Every drivetrain part on this page is engine-specific. Each row shows which engine(s) it fits — use the filter at the top to hide the rest. If you're unsure which engine you have, check the emissions label under the hood or the 8th character of your VIN.
What are the signs of drivetrain problems on a 2021 Audi A4?
Common symptoms include clicking in tight turns, a clunk when shifting between drive and reverse, vibration that builds with speed, or gear oil on the inside of a wheel. If you notice any of these, identify the affected subcategory above and cross-reference the part numbers listed.
What should I replace at the same time?
Where labor overlaps, replace the differential or transfer-case fluid with any axle or seal job while everything is already open.
What do the market flags (US, CA, MX) on each part mean?
They show the market for which the manufacturer published application data for that part — where the vehicle was first sold, not where the part was made. If your 2021 Audi A4 was originally sold in the US, the safest choice is a part marked for the US market.
How do I make sure a part fits my 2021 Audi A4?
First match the engine — each row shows which engine(s) the part fits. Then a torn CV boot caught early is a cheap boot kit; caught late it is a whole axle — inspect before deciding which to buy. The notes column carries position and trim qualifiers where they apply.
Other Parts for the 2021 Audi A4
Drivetrain Parts for Other Audi A4 Years
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