# Pololu #4756 131:1 37D Gearmotor

> Pololu #4756 is a 12 V brushed DC 37D metal gearmotor with 131.25:1 reduction (helical first stage), 76 rpm no-load output, 45 kg·cm extrapolated stall torque, 5.5 A extrapolated stall current, 6 mm D-shaft, a 64 CPR Hall quadrature encoder on the motor shaft (8400 CPR at the output), 37 mm × 72.5 mm, 210 g.

- Manufacturer: Pololu
- Part number: 4756
- Category: Motors
- Canonical page: https://www.xirkit.io/products/pololu-4756-131-1-37d-gearmotor-e435
- Pinout: https://www.xirkit.io/products/pololu-4756-131-1-37d-gearmotor-e435/pinout
- Structured JSON: https://www.xirkit.io/products/pololu-4756-131-1-37d-gearmotor-e435/data.json
- Source: Xirkit structured parts catalog — every value traced to a cited document; unknowns are explicit.

## Key specifications

| Property | Value |
| --- | --- |
| Motor type | gearmotor |
| Rated voltage | 12 V |
| Stall torque | 4.413 N·m |
| No-load speed | 76 rpm |
| Gear ratio | 131.25:1 |
| Shaft diameter | 6 mm |
| Encoder | Hall quadrature encoder; 64 CPR at motor shaft, 8400 CPR at output shaft |
| Dimensions | 37 × 37 × 88.5 mm |
| Certifications | RoHS 3 compliant |

## Pinout (6 pins, 0 with electrical limits)

| Pin | Position | Kind | Chip pad | Functions | VIH | VIL | VOH | VOL | IOH | IOL | 5 V tolerant |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Red | 1x6 female 2.54 mm header | motor plus | — | red | — | — | — | — | — | — | — |
| Black | 1x6 female 2.54 mm header | motor minus | — | black | — | — | — | — | — | — | — |
| Green | 1x6 female 2.54 mm header | ground | — | ground | — | — | — | — | — | — | — |
| Blue | 1x6 female 2.54 mm header | supply | — | blue | — | — | — | — | — | — | — |
| Yellow | 1x6 female 2.54 mm header | signal | — | yellow | — | — | — | — | — | — | — |
| White | 1x6 female 2.54 mm header | signal | — | white | — | — | — | — | — | — | — |

## Where to buy

| Supplier | Price | Stock | Checked | URL |
| --- | --- | --- | --- | --- |
| www.pololu.com | 60.95 USD | in_stock | 2026-10-01 | https://www.pololu.com/product/4756 |

## FAQ

**How much does the Pololu #4756 131:1 37D Gearmotor cost?**

From $60.95 at www.pololu.com. Prices are observed unit prices before tax and shipping.

**What are the Pololu #4756 131:1 37D Gearmotor dimensions?**

37 × 37 × 88.5 mm. A STEP model is available for enclosure fit checks.

**Where does this Pololu #4756 131:1 37D Gearmotor data come from?**

Every value in this record is traced to a source — 2 documents including the board and chip datasheets — with the page and table cited per value. Unknowns are left explicit, never guessed.

## Sources

- [Pololu #4756 131:1 37D Gearmotor datasheet](https://www.pololu.com/file/0J1706/pololu-37d-metal-gearmotors.pdf)
- [www.pololu.com listing](https://www.pololu.com/product/4756)

## Part graph

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