| Manufacturer | Rolex |
| Caliber Number | 3185 |
| Base Caliber |
3135 |
| Movement Type | Automatic, self-winding mechanical |
| In-House? | Yes |
| Diameter | 28.5mm |
| Height |
6.45mm |
| Jewels | 31 |
| Vibrations Per Hour | 28,800 (4Hz) |
| Hacking Seconds? |
Yes |
| Rotor Direction | Bidirectional |
| Shock System | KIF Elastor |
| Features | Central hours; central minutes; central sweeping seconds; central independent GMT hand; date at 3:00 |
| Country of Manufacture | Switzerland, Swiss made |
| Known Models | Rolex GMT-Master II (16710), Rolex Explorer II |
The Rolex caliber 3185 is a Swiss made automatic GMT movement with a quickset date. This movement is based on the popular Rolex 3135 framework with an additional 24 hour hand for the GMT complication.
The 3185 was first introduced in the 16710 GMT-Master II in 1989 (1988?). It was upgraded to the 3186 circa 2005-2006.
In Rolex’s own words:
“Created in response to demand from professional aviators, the GMT-Master II is equipped with a device for rapidly moving the normal hour hand in one-hour jumps. This makes it possible to momentarily display the time in a time zone different to the two that have previously been set.” -Rolex
3085 VS 3185:
There is a similar Rolex GMT movement called the caliber 3085. It was based on the 3035, and was used Notable differences between the Rolex caliber 3185 and the 3085 are that the 3185 has 31 jewels and the 3085 has 27 jewels. The 3085 is a taller movement at 7.2mm vs 6.45mm. This is why it is found in the so-called “Fat Lady” GMT-Master II models with a thicker case.
Regulating the 3185:
It is recommended to have a professional make necessary adjustments to your Rolex watch. If you want to DIY adjust the timing of the caliber 3185, you will need a Microstella tool to do so. When making adjustments, always remember that it is crucial to make identical adjustments on two Microstella nuts that are opposite of each other on the balance wheel, otherwise the balance will be thrown out of poise.
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