67:1 Metal Gearmotor 37Dx54L mm

This 2.13" x 1.45" x 1.45" gearmotor is a powerful brushed DC motor with 67:1 metal gearbox intended for operation at 12 V. These units have a 0.61"-long, 6 mm-diameter D-shaped output shaft. This gearmotor is also available with an integrated encoder. Key specs at 12 V: 150 RPM and 300 mA free-run, 200 oz-in (14 kg-cm) and 5 A stall.

Gearmotor Options

This powerful brushed DC gearmotor is available in six different gear ratios. A version with an integrated encoder is also available.
Gear Ratio       Speed  
@ 12V     Stall Torque
@ 12V     Stall Current
@ 12V     


                     With Encoder                        Without Encoder
19:1     500 RPM     84 oz-in     5 A     37Dx52L mm     37Dx52L mm
29:1     350 RPM     110 oz-in     5 A     37Dx52L mm     37Dx52L mm
50:1     200 RPM     170 oz-in     5 A     37Dx54L mm     37Dx54L mm
67:1     150 RPM     200 oz-in     5 A     37Dx54L mm     37Dx54L mm
100:1     100 RPM     220 oz-in     5 A     37Dx57L mm     37Dx57L mm
131:1     80 RPM     250 oz-in     5 A     37Dx57L mm     37Dx57L mm

These motors are intended for use at 12 V, though the motor can begin rotating at voltages as low as 1 V.
Gearmotor Dimensions:

The face plate has six mounting holes evenly spaced around the outer edge threaded for M3 screws. These mounting holes form a regular hexagon and the centers of neighboring holes are 15.5 mm apart. You can use our custom 37D metal gearmotor bracket (shown in the left picture below) to mount the gearmotor to your project via these mounting holes and the screws that come with the bracket.
Gearmotor with bracket and hub.
Black Pololu 90×10mm wheel on a Pololu 37D mm metal gearmotor.

Please note that unlike our smaller metal gearmotors, these 37D mm gearmotors have output shafts with a diameter of 6 mm. The Pololu universal aluminum mounting hub for 6mm shafts can be used to mount our larger Pololu wheels (80mm- and 90mm-diameter) or custom wheels and mechanisms to the gearmotor’s output shaft (see the right picture above).

The picture below shows the dimensions (in mm) of the 37D mm line of gearmotors. The value of X is 22 mm for the 19:1 37Dx52L mm and 29:1 37Dx52L mm versions, 24 mm for the 50:1 37Dx54L mm and 67:1 37Dx54L mm versions, and 26.5 mm for the 100:1 37Dx57L mm and 131:1 37Dx57L mm versions.

37D mm metal gearmotor dimensions (units in mm).

Warning: Do not screw too far into the mounting holes as the screws can hit the gears. We recommend screwing no further than 3mm (1/8") into the screw hole.

The operational specs listed in the table below were measured at 6 V. At 12 V, the no-load RPM, stall current, and stall torque will all be approximately twice their 6V values. To see the motor specs for 12V operation, please see the short description at the top of this page or this product’s specification tab.

37D mm metal gearmotor next to a micro metal gearmotor for size comparison.




Size:     37D x 54L mm
Weight:     6.9 oz
Shaft diameter:     6 mm

General specifications

Gear ratio:     67:1
Free-run speed @ 6V:     75 rpm1
Free-run current @ 6V:     250 mA1
Stall current @ 6V:     2500 mA1
Stall torque @ 6V:     100 oz·in1
Free-run speed @ 12V:     150 rpm
Free-run current @ 12V:     300 mA
Stall current @ 12V:     5000 mA
Stall torque @ 12V:     200 oz·in


1    This motor will run at 6 V but is intended for operation at 12 V.