The 2021 BMW M3 has 19 belt drive parts with verified fitment on this page — 3 part types and 10 brands, covering the 3.0L L6 Turbocharged engine. Each part includes a manufacturer part number and application notes.
On the 2021 BMW M3, the belt drive system spins the accessories — serpentine and V-belts, tensioners, idlers and pulleys. All 19 listed parts are Belt (8 parts), Idler Pulley (7 parts) and Belt Tensioner (4 parts).
Every part on this page is matched to the 3.0L L6 Turbocharged — the only engine offered in the 2021 BMW M3.
The most listed brands for 2021 BMW M3 belt drive parts are CONTINENTAL (4 parts), GATES (3 parts) and DAYCO (3 parts), plus 7 more brands. Quality grades include Standard Replacement and Economy.
4 parts on this 2021 BMW M3 page carry a "Popular" badge — the source catalog's flag for options frequently chosen for this vehicle — including CONTINENTAL 465K6MK (Belt) and CONTINENTAL 50069 (Idler Pulley). Click any part number to see every vehicle that part fits.
Belt
Economy
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| CONTINENTAL Popular | 465K6MK | 🇺🇸 US 🇨🇦 CA | Mileage MakerSerpentine | View on Amazon |
| GATES Popular | K060465 | 🇺🇸 US 🇨🇦 CA | Micro-V | View on Amazon |
| DAYCO | 5060465DR | 🇺🇸 US 🇨🇦 CA | Drive Rite®Serpentine | View on Amazon |
| FVP | 465K6 | 🇺🇸 US 🇨🇦 CA | Multi V-BeltSerpentine | View on Amazon |
| ROADMAX | 6K465AP | 🇺🇸 US 🇨🇦 CA | V-RibbedSerpentine | View on Amazon |
Standard Replacement
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| ACDELCO | 6K465 | 🇺🇸 US 🇨🇦 CA | Professional / GoldSerpentine | View on Amazon |
| CONTINENTAL | 4060465 | 🇺🇸 US 🇨🇦 CA | Multi V-BeltSerpentine | View on Amazon |
| DAYCO | 5060465 | 🇺🇸 US 🇨🇦 CA | Serpentine | View on Amazon |
This table covers the serpentine and accessory belts that drive the front accessories. Typical signs include squeal on cold start, cracks across the ribs, or glazing on the back of the belt. A new belt on a worn tensioner will squeal within weeks — spin the idlers by hand while the belt is off.
8 Belt parts are listed for the 2021 BMW M3, from CONTINENTAL, DAYCO, GATES and 3 other brands. CONTINENTAL 465K6MK carries the "Popular" badge.
In the Economy grade, CONTINENTAL, GATES, DAYCO and 2 other brands supply 5 parts: the catalog's value-priced group. A representative part number is CONTINENTAL 465K6MK.
The Standard Replacement section lists 3 options from ACDELCO, CONTINENTAL and DAYCO — built to original-equipment specification. ACDELCO 6K465 is listed in this group.
This group includes CONTINENTAL 465K6MK, GATES K060465 and DAYCO 5060465DR and the remaining parts above.
Belt Tensioner
Economy
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| ULTRA-POWER | 39381 | 🇺🇸 US 🇨🇦 CA | View on Amazon |
Standard Replacement
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| CONTINENTAL | 49878 | 🇺🇸 US 🇨🇦 CA | Multi-V | View on Amazon |
| GATES | 39381 | 🇺🇸 US 🇨🇦 CA | View on Amazon | |
| LITENS | 999682A | 🇺🇸 US 🇨🇦 CA | View on Amazon |
This table covers the automatic tensioners that hold belt tension. Typical signs include belt flutter, a chirp that returns after a new belt, or a damper that no longer holds the arm. Replace the tensioner with the belt at higher mileage; the labor overlaps almost entirely.
4 Belt Tensioner parts for the 2021 BMW M3 come from 4 brands — ULTRA-POWER, CONTINENTAL, GATES and 1 other brand.
The Economy section: 1 option from ULTRA-POWER. ULTRA-POWER 39381 is listed in this group.
Standard Replacement: 3 parts, from CONTINENTAL, GATES and LITENS. A representative part number is CONTINENTAL 49878.
Listed part numbers: ULTRA-POWER 39381 and CONTINENTAL 49878, plus the other parts above.
Idler Pulley
Economy
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| ÜRO PARTS | 11288673720 | 🇺🇸 US 🇨🇦 CA | View on Amazon | |
| VAICO | V202769 | 🇺🇸 US 🇨🇦 CA | Material Type: Plastic | View on Amazon |
Standard Replacement
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| CONTINENTAL Popular | 50069 | 🇺🇸 US 🇨🇦 CA | SmoothIncludes Hardware | View on Amazon |
| LITENS Popular | 900680A | 🇺🇸 US 🇨🇦 CA | Smooth | View on Amazon |
| ACDELCO | 36728 | 🇺🇸 US 🇨🇦 CA | Professional / Gold | View on Amazon |
| DAYCO | 89551 | 🇺🇸 US 🇨🇦 CA | Smooth | View on Amazon |
| GATES | 36728 | 🇺🇸 US 🇨🇦 CA | Smooth | View on Amazon |
This table covers the idler pulleys the belt wraps around. Typical signs include a chirp that follows engine speed, or a pulley that feels rough or has play. Replace a noisy idler with the belt — the labor is already paid for.
7 Idler Pulley parts are listed for the 2021 BMW M3, from ÜRO PARTS, VAICO, CONTINENTAL and 4 other brands. CONTINENTAL 50069 carries the "Popular" badge.
Economy: 2 parts, from ÜRO PARTS and VAICO. A representative part number is ÜRO PARTS 11288673720.
The Standard Replacement section: 5 options from CONTINENTAL, LITENS, ACDELCO and 2 other brands. CONTINENTAL 50069 is listed in this group.
This group includes CONTINENTAL 50069, ÜRO PARTS 11288673720 and VAICO V202769 and the remaining parts above.
Buying Belt Drive Parts for a 2021 BMW M3
On this vehicle, the belt drive system spins the accessories — serpentine and V-belts, tensioners, idlers and pulleys.
- Confirm you have the 3.0L L6 Turbocharged engine — every part on this page is matched to it.
- Read the notes on each row for position, trim and spec qualifiers before you order.
- Where labor overlaps, replace the tensioner and idler pulleys with any belt at higher mileage — the labor overlaps almost entirely.
- Cross-reference the manufacturer part number against your old part or a service-manual listing.
Start with the largest groups on this page: Belt and Idler Pulley .
Frequently Asked Questions
How many belt drive parts fit the 2021 BMW M3?
Our catalog currently lists 19 belt drive parts for the 2021 BMW M3 across 3 subcategories and 10 brands, covering the 3.0L L6 Turbocharged engine. Each part is matched to the engine(s) it fits.
What are the signs of belt drive problems on a 2021 BMW M3?
Common symptoms include squealing on cold start, a belt that shows cracking or glazing, or an accessory that slows under load. 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 tensioner and idler pulleys with any belt at higher mileage — the labor overlaps almost entirely.
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 BMW M3 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 BMW M3?
Every part on this page is matched to the 3.0L L6 Turbocharged engine. Then a new belt on a worn tensioner will squeal within weeks — check tensioner damping and idler bearings while the belt is off. The notes column carries position and trim qualifiers where they apply.
Other Parts for the 2021 BMW M3
Belt Drive Parts for Other BMW M3 Years
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Manufacturer names, model designations and part numbers are used for identification and fitment reference only. AutoFactsDB is an independent catalog and is not affiliated with, endorsed by, or sponsored by any vehicle manufacturer displayed on this page.