On a similar note to some of these, Google recommends you use Johnston Rd to shortcut around US-95 in Grangeville, ID.
Maps Link. Saves about 3 miles and a lot of people use it. The pavement is in rough shape, and it is posted at 35 MPH (lower than you'd expect for a road like this) and I believe No Thru Trucks. Not sure if it's always been that way. I've used it, but I think I prefer just going through Grangeville, plus it's a decent gas stop, and there's a Taco John's there which I like to stop at since the ones near Boise closed.
Here's an even bigger shortcut near Susanville, CA, it saves 10 miles compared to staying on US-395.
Maps Link. You definitely want to use this shortcut (I've been on it, but around a decade ago), it's paved and looks to be posted at 55 MPH.