I'm due December 28 th and I live in Lovelock Nevada. I'm going to sac this Saturday and was wondering if going from an elavation of 4000 ft to 246 feet will induce labor

No, it won't induce labor. You'll actually be a bit higher going into California, but if changes in elevation induced labor, you would have mothers driving up and down trying to get things going. Consider the number of women who fly towards the last weeks of pregnancy. Elevation changes are obviously far greater.
Let your doctor or midwife know your plans. More than likely they will be fine with it as you can have a baby just as well in Sac as you can in Lovelock... :) Main consideration, since it is a few hours drive, would be to stop about every hour to get out and walk around a bit, have drinks and snacks with you, and make sure you have warm clothing.

When I was 39 weeks pregnant with my son I went camping I lived in sac and went to lassen park and 2 days later he was born. The day before I left I was checked and I wasn't thinning out or dialating.

>>>>>>When I was 39 weeks pregnant with my son I went camping I lived in sac and went to lassen park and 2 days later he was born. The day before I left I was checked and I wasn't thinning out or dialating.

39 weeks is a perfectly normal time for you to give birth. I went to a cabin up in Big Bear a few weeks before my due date with my fourth. Doctor was fine with it.

Some women will get checked and their cervix will be closed and firm. Doctor says I'll see you next week, and mom goes into labor the next day. Other women will walk around the last few weeks of pregnancy already 3 cm dilated. It really means very little to be checked at the end of pregnancy other than to give them a heads-up if there were any changes starting.

Give your doctor or midwife a call and see what they suggest. The concern that sometimes comes up is just being that far away from where they are if you were to happen to go into labor, not that the trip would cause you to go into labor. If they are fine with you going, enjoy your trip!