Welcome!
I've traveled Hwy 58 many times towing my 14K 5vr w/o any issues
Also been up/down I-5
Course my 14K 5vr is well within my 2007 3500 towing abilities.
Wish you had joined/asked question prior to buying that 5vr.
Very nice 5th wheel but it is too heavy for your truck. Sorry
That Momentum 'dry weight' (12,400#) is only 800/1300# under your trucks MAX Tow rating (which is a magical mfg. marketing number)------hope you have good braking for the pass
Truck is going to be overloaded.
Realty check......
Go get it weighed 'camp ready' truck/trailer loaded up for trip.
Cat Scales....Front/Rear Axle weights---Total truck/trailer and then just truck ($10/12)
Compare actual weight numbers against your trucks GVWR, Axle Weight Ratings, Tire Max Load Ratings
Good luck/stay safe