Thanks everyone. We're coming up 395, through Mammoth and Lee Vining, then probably staying in South Lake Tahoe, though we haven't booked a campground yet.
We have some friends who've decided to rent a smaller Class-A and come with us, but they won't be towing. And that means 8 people instead of 4, so I'll have my Suburban on the trailer, rather than my Jeep. It's quite a bit heavier, but the trailer has good brakes (electric on both axles, rated for 10K) so I'm not terribly concerned.
Based on your comments, I'm thinking that we can take Hwy 50 from South Lake Tahoe to Sacramento, as whatever speed I'm doing in the DP & trailer he can do in the rental.
I'll give him some guidance on using the transmission to slow on the downgrades, rather than the brakes.
2003 Country Coach Intrigue, Cummins ISL 400
Toad: 2006 Jeep Wrangler Unlimited (LJ) toad, with just a few mods...
Other rig: 2005 Chevy Silverado 3500 Duramax Dually / Next Level 38CK Fifth-wheel Toy Hauler w/ quads, sand rail, etc...