Hi PM6163 -
<<" I plan to take Golden Pass as a day trip from Lucerne, is that too rush? one way will take 5 hours from Lucerne to Montreux.">>
It seems that you have been checking the timetable and can see the 5 hours and 8 minutes required for the Golden Pass routing:
If not, you can use it to help answer your question. If you enter Lucerne or Luzern as your start point and Montreux as your destination, without entering anything in the "via" or "connections" box, the computer will default to the fastest route between start and destination.
( I prefer to use the German spelling, since that is what you will see on signs in the German speaking regions including the area surrounding Zürich and Luzern; Lucerne is the French spelling and you will likely see that when you are in Montreux.)
In order to get the plan for the trains on the Golden Pass Route, you can use the "Advanced Search" option and put in two intermediate stops. Use Meiringen ( between Luzern and Interlaken Ost, and also Zweisimmen ( between Interlaken Ost (IO) and Montreux).
Lots of details in the tabs at this URL:
If you choose not to use the advanced search option, you may search twice...Luzern to IO via Meiringen and, separately, IO to Montreux via Zweisimmen.
You will see "Luzern-Interlaken Express" which runs on the the Golden Pass route as the default for that section.
That part takes 1 hour and 50 minutes.
A map can help you visualize these routings:
A map of the route is also available in the footnotes, once you have expanded any single journey by clicking on the "+" sign to the left of the journey in the first screen that appears in your search.
Once you have reached IO, the computer will want to route you via Spiez and Visp, then along the Rhone Valley. That takes 2 hours and 15 to 20 minutes via Spiez and Visp.
The routing is also offered - IO-Bern- Lausanne - Montreux takes 2 hors and approximately 40 minutes
The route via Zweisimmen takes 3 hours 13 minutes or 3 hours 44 minutes. These sections have delay due to track work, and a bus is substituted for part of the trip. A nuisance if you have luggage to load and unload; not a problem on a day trip.
The purpose of this anaysis is to show that you might return from Montreux to Luzern on shorter routes, which could save some time compared to the Golden Pass Routing. For example - the routing Montreux to Luzern, without any way points selected in the timetable, goes through Lausanne (change trains) thence to Luzern via Bern, Zofingen, etc., using high speed sections of track and takes 2 hrs 37 minutes once per hour at xx23. Or, there is slightly slower route -3 hours 7 minutes via Olten, with two changes departing Montreux at xx48.
Is it too rushed?
That depends on you. 5 hours 8 minutes to Montreux, and the fastest return of 2 hrs 37 minutes adds up to 7 hrs 45 minutes on the trains. How early do you want to get up, and how early do you want to return?
What will you do at or near Montreux?
When are you traveling? In December, it gets dark at about 1630. The return trip could be completely in the dark. Today, sunset is at 1927.