Grapevine Summit is 4144'.
Here I5 drops sharply. The truck speed limit is 45, and cars have to slow to 55 then 45 later on.
About Mile 201. This is from 11/25/2008. The hills are going green
in the photos from this day.
This is about Mile 199 and near 138, which leads to I15 and beyond.
I have been told 58 is faster than 138.
South in Los Angeles County (Grapevine)