This page lists 14 belt drive parts for the 2021 GMC Terrain, across 2 part types, covering both the 1.5L L4 Turbocharged and the 2.0L L4 Turbocharged. Every part shows its brand, manufacturer part number and fitment notes.
On the 2021 GMC Terrain, the belt drive system spins the accessories — serpentine and V-belts, tensioners, idlers and pulleys. All 14 listed parts are Belt Tensioner (8 parts) and Belt (6 parts).
The 2021 GMC Terrain was sold with both the 1.5L L4 Turbocharged and the 2.0L L4 Turbocharged. 1 part fits every engine; the other 13 are engine-specific. Each part shows which engine(s) it fits.
The most listed brands for 2021 GMC Terrain belt drive parts are ACDELCO (3 parts), CONTINENTAL (2 parts) and DAYCO (2 parts), plus 5 more brands. Quality grades include Standard Replacement and Economy.
4 parts on this 2021 GMC Terrain page carry a "Popular" badge — the source catalog's flag for options frequently chosen for this vehicle — including ACDELCO 12654472 (Belt) and GATES 39375 (Belt Tensioner). Click any part number to see every vehicle that part fits.
Belt
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| ACDELCO Popular Fits: all 2021 Terrain engines | 12654472 | 🇺🇸 US 🇨🇦 CA | GM Original EquipmentSerpentine | View on Amazon |
| ACDELCO Popular Fits: 1.5L L4 Turbocharged | 5K689 | 🇺🇸 US 🇨🇦 CA | Professional / GoldSerpentine | View on Amazon |
| BANDO Fits: 1.5L L4 Turbocharged | 5PK1750 | 🇺🇸 US 🇨🇦 CA | Rib Quantity: 5Effective Length: 1750.0 mm | View on Amazon |
| CONTINENTAL Fits: 1.5L L4 Turbocharged | 4050689 | 🇺🇸 US 🇨🇦 CA | Multi V-BeltSerpentine | View on Amazon |
| DAYCO Fits: 1.5L L4 Turbocharged | 5050689 | 🇺🇸 US 🇨🇦 CA | Serpentine | View on Amazon |
| GATES Fits: 1.5L L4 Turbocharged | K050689 | 🇺🇸 US 🇨🇦 CA | Micro-V | 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.
6 Belt parts are listed for the 2021 GMC Terrain, from ACDELCO, BANDO, CONTINENTAL and 2 other brands. ACDELCO 12654472 carries the "Popular" badge. 1 part fits every engine; the other 5 are engine-specific.
Listed part numbers: ACDELCO 12654472, ACDELCO 5K689 and BANDO 5PK1750, plus the other parts above.
Belt Tensioner
Economy
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| ULTRA-POWER Fits: 1.5L L4 Turbocharged | 39375 | 🇺🇸 US 🇨🇦 CA | View on Amazon |
Standard Replacement
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| GATES Popular Fits: 1.5L L4 Turbocharged | 39375 | 🇺🇸 US 🇨🇦 CA | View on Amazon | |
| GM GENUINE Popular Fits: 1.5L L4 Turbocharged | 12638689 | 🇺🇸 US 🇨🇦 CA | View on Amazon | |
| ACDELCO Fits: 1.5L L4 Turbocharged | 39375 | 🇺🇸 US 🇨🇦 CA | Professional / Gold | View on Amazon |
| CONTINENTAL Fits: 1.5L L4 Turbocharged | 49846 | 🇺🇸 US 🇨🇦 CA | Multi-V | View on Amazon |
| DAYCO Fits: 1.5L L4 Turbocharged | 89744 | 🇺🇸 US 🇨🇦 CA | View on Amazon | |
| LITENS Fits: 1.5L L4 Turbocharged | 999622A | 🇺🇸 US 🇨🇦 CA | View on Amazon |
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| GM GENUINE Fits: 2.0L L4 Turbocharged | 12638689 | 🇺🇸 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.
8 Belt Tensioner parts for the 2021 GMC Terrain come from 7 brands — GM GENUINE, ULTRA-POWER, GATES and 4 other brands. The "Popular" part is GATES 39375.
The Economy section lists 1 option from ULTRA-POWER — the catalog's value-priced group. ULTRA-POWER 39375 is listed in this group.
In the Standard Replacement grade, GATES, GM GENUINE, ACDELCO and 3 other brands supply 6 parts: built to original-equipment specification. A representative part number is GATES 39375.
1 further part sits outside the graded sections, with the same engine-level match.
Part numbers include GATES 39375 and GM GENUINE 12638689, among others listed above.
Buying Belt Drive Parts for a 2021 GMC Terrain
On this vehicle, the belt drive system spins the accessories — serpentine and V-belts, tensioners, idlers and pulleys.
- Match the engine first. Some belt drive parts fit every engine; others are 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 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 Tensioner and Belt .
Frequently Asked Questions
How many belt drive parts fit the 2021 GMC Terrain?
Our catalog currently lists 14 belt drive parts for the 2021 GMC Terrain across 2 subcategories and 8 brands, covering both the 1.5L L4 Turbocharged and the 2.0L L4 Turbocharged. Each part is matched to the engine(s) it fits.
Do belt drive parts differ between 2021 GMC Terrain engines?
Some do. 1 part fits every engine; the other 13 are engine-specific. Each row (and the filter at the top) shows which. 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 belt drive problems on a 2021 GMC Terrain?
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 GMC Terrain 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 GMC Terrain?
First match the engine — each row shows which engine(s) the part fits. 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 GMC Terrain
Belt Drive Parts for Other GMC Terrain 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.