This page lists 21 belt drive parts for the 2021 Mazda CX-3, across 4 part types, covering the 2.0L L4 engine. Every part shows its brand, manufacturer part number and fitment notes.
The belt drive system on the 2021 Mazda CX-3 spins the accessories — serpentine and V-belts, tensioners, idlers and pulleys. The largest groups are Belt (12 parts), Belt Tensioner (6 parts) and Belt Removal / Installation Tool (2 parts). The other 1 part type covers the remaining 1 part.
Every part on this page is matched to the 2.0L L4 — the only engine offered in the 2021 Mazda CX-3.
The most listed brands for 2021 Mazda CX-3 belt drive parts are CONTINENTAL (5 parts), GATES (5 parts) and DAYCO (4 parts), plus 5 more brands. Quality grades include Standard Replacement, Economy and Kit.
5 parts on this 2021 Mazda CX-3 page carry a "Popular" badge — the source catalog's flag for options frequently chosen for this vehicle — including CONTINENTAL 4030317S (Belt) and GATES 90K39390 (Belt Tensioner). Click any part number to see every vehicle that part fits.
Belt
Economy
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| CONTINENTAL | 380K6MK | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | Mileage MakerSerpentine | View on Amazon |
| DAYCO | 5060380DR | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | Drive Rite®Serpentine | View on Amazon |
| FVP | 380K6 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | Multi V-BeltSerpentine | View on Amazon |
Standard Replacement
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| CONTINENTAL Popular | 4030317S | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | Multi V-Belt Stretch Belt | View on Amazon |
| GATES Popular | K060378 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | Micro-V | View on Amazon |
| GATES Popular | K030309SF | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | Premium OE Stretch Fit Micro-V Belt | View on Amazon |
| ACDELCO | 6K378 | 🇺🇸 US 🇨🇦 CA | Professional / GoldSerpentine | View on Amazon |
| BANDO | 6PK960 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | Rib Quantity: 6 | View on Amazon |
| CONTINENTAL | 6PK976 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | Metric LineSerpentine | View on Amazon |
| CONTINENTAL | 4060380 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | Multi V-BeltSerpentine | View on Amazon |
| DAYCO | 3PK794EE | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | ELA® Stretch BeltSerpentine | View on Amazon |
| DAYCO | 5060380 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | 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.
12 Belt parts are listed for the 2021 Mazda CX-3, from CONTINENTAL, DAYCO, GATES and 3 other brands. CONTINENTAL 4030317S carries the "Popular" badge.
In the Economy grade, CONTINENTAL, DAYCO and FVP supply 3 parts: the catalog's value-priced group. A representative part number is CONTINENTAL 380K6MK.
The Standard Replacement section lists 9 options from CONTINENTAL, GATES, DAYCO and 2 other brands — built to original-equipment specification. CONTINENTAL 4030317S is listed in this group.
Belt Removal / Installation Tool
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| ACDELCO | 91030 | 🇺🇸 US 🇨🇦 CA | Professional / GoldMicro-V Stretch Fit Installation Tool | View on Amazon |
| GATES | 91030 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | Micro-V Stretch Fit Installation Tool | View on Amazon |
This table covers the Belt Removal / Installation tools. This is a service tool, not a wear part — match the application in the notes.
2 Belt Removal / Installation Tool parts for the 2021 Mazda CX-3 come from 2 brands — ACDELCO and GATES.
Part numbers include ACDELCO 91030, among others listed above.
Belt Tensioner
Kit
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| GATES Popular | 90K39390 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | KitIncludes: 2 Belts, Tensioner | View on Amazon |
Standard Replacement
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| LITENS Popular | 999630A | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | View on Amazon | |
| ACDELCO | 39390 | 🇺🇸 US 🇨🇦 CA | Professional / Gold | View on Amazon |
| CONTINENTAL | 49858 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | Multi-V | View on Amazon |
| DAYCO | 89710 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | View on Amazon | |
| GATES | 39390 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | 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.
6 Belt Tensioner parts for the 2021 Mazda CX-3 come from 5 brands — GATES, LITENS, ACDELCO and 2 other brands. The "Popular" part is GATES 90K39390.
The Kit section lists 1 option from GATES — grouped under the catalog's "Kit" designation — the notes column spells out what sets them apart. GATES 90K39390 is listed in this group.
Standard Replacement: 5 parts, from LITENS, ACDELCO, CONTINENTAL and 2 other brands. A representative part number is LITENS 999630A.
Listed part numbers: GATES 90K39390, LITENS 999630A and ACDELCO 39390, plus the other parts above.
Belt Tensioner Adjuster
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SKP | SK90K39390 | 🇺🇸 US 🇨🇦 CA 🇲🇽 MX | View on Amazon |
This table covers the Belt Tensioner adjusters.
This group shows a single part: SKP SK90K39390.
Buying Belt Drive Parts for a 2021 Mazda CX-3
On this vehicle, the belt drive system spins the accessories — serpentine and V-belts, tensioners, idlers and pulleys.
- Confirm you have the 2.0L L4 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 Belt Tensioner .
Frequently Asked Questions
How many belt drive parts fit the 2021 Mazda CX-3?
Our catalog currently lists 21 belt drive parts for the 2021 Mazda CX-3 across 4 subcategories and 8 brands, covering the 2.0L L4 engine. Each part is matched to the engine(s) it fits.
What are the signs of belt drive problems on a 2021 Mazda CX-3?
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 Mazda CX-3 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 Mazda CX-3?
Every part on this page is matched to the 2.0L L4 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 Mazda CX-3
Belt Drive Parts for Other Mazda CX-3 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.