How is my 2019 GMT II running?

[HiBoost]

Originally Posted by NKflyer

I’m not a watchmaker so take this with a grain of salt. What what I’ve always heard and personally observed is that a new Rolex or one recently serviced by a top-notch watchmaker should have amplitude approximately ~300 degrees when fully wound. On the other hand, once you get down to 230-240 degrees, it’s indisputably time for a movement overhaul.

Yours seems in the ballpark for a five year old Rolex, if perhaps a little low. Are you testing it on a decent timegrapher and manually winding via the crown 40 turns before testing? Newer synthetic oils last a long time so service intervals are longer than in the past. Ten year service intervals aren’t out of the question, at all.

300 is about the max you'd expect with an older 31xx movement. The 32xx runs at lower amplitude, generally speaking. It also has a different lift angle so you'd need to change the timegrapher settings to know exactly was the amplitude is.

As far as 230-240 being "indisputably" time for a service, keep in mind it depends on position. That amplitude range with the watch in a vertical position is totally normal for a 32xx (and again a bit low for a 31xx). My fresh-from-RSC 3285 does around 235 at full wind when the crown is down. It does 273 with the dial up.