I have recently returned to the PNW after a few couiple of years in Europe.
I glimpsed an Amtrak Cascade service train while driving on I-5 north of Everett WA, what I saw did not look like Talgo cars. I-5 is approx a mile from the RR , so observations were difficult to make while safley driving on that crazy road !
I haven’t heard about any change in the equipment away from the Talgo cars. The are replaced from time to time with other equipement for maintenance purposes. I will say that the Talgo cars I have been in recently are starting to look a little worn inside.
While eating dinner in a Thai restraunt near to the mainline in Stanwood on Saturday, I saw the evening Northbound Cascade with what appeared to be 3 Superliner cars rather than the expected Talgo cars. Again, it was seen at a glance rather than true line side as I was enjoying a great tasting (and HOT) Green Curry with my Wife, so no photos !
The Cascades operate with an EMD power unit on one end (usually the South) and a converted F40PH “dummie” cab car on the other, Behind each locomotive (real and pretend) is a “stepdown” car, one end of which is standard Talgo and the other end is standard US. Between is the Talgo equipment.
This equipment usually operates without a relief set of Talgo equipment, relying instead on the only full length dome left in AMTK service with three Amfleet coaches on each end. Not push pull.
However, with the equipment shortage caused by the Acela problem, this relief trainset is now in the East and 2 or 3 Superliner coaches subing.