I'm taking the Zephyr from Chicago to San Francisco and making a few stops on the way, one of them being Truckee CA. We planned on driving from Truckee to Lake Tahoe and staying there on Friday night. Then we would drive to Yosemite on Saturday for the day and go back and stay in Lake Tahoe Saturday night. On Sunday morning we would take the train the rest of the way to Emeryville. I don't really want to go to San Fran if I don't have to because I've already been there before and after we leave there we are driving down the coast to LA where I have never been before. I was wondering if it would be a good idea to just skip the train from Truckee to San Fran and just drive straight to Big Sur our first stop down the coast and have extra time in Yosemite in the middle. Would I be missing awesome views on the train from Truckee to Emeryville or would it be ok if I drove.

Before anyone can help you much we need to know what time of year. But >>Then we would drive to Yosemite on Saturday for the day and go back and stay in Lake Tahoe Saturday night.

NO, you will NOT miss any fabulous views IMO.

Get off and rent your car in either Reno or Sacramento.
Which end of Lake Tahoe do you want to go to?
The scenery is nice in the Sierras west of Reno but nothing to compare with Yosemite.
The greatest scenery to see from the California Zephyr is in the Glenwood Canyon east of Glenwood Springs Colorado.
Get lodging in or near Yosemite and not in South Lake Tahoe.
If this is a winter trip, you may not be able to drive where you want in Yosemite.
Are you going back to Chicago after your time in LA?

You will not miss anything after Truckee. You will miss our "fabulous" Emeryville