From the Colorado section of the Mountain Directory West

 

The descent on the westbound side of Vail Pass is about 10 miles in length and begins at milepost 189 on I-70. One half mile west of the summit there are warning signs for westbound traffic--"Speed limit 45 mph for vehicles over 30,000 lbs." and "Steep grade next 8 miles--trucks stay in lower gear."  The next mile is rolling hills.  Then there is a sign--"7% grade next 7 miles."

The descent is steady at 7% and there are 3 advisory signs for the first runaway truck ramp which is about milepost 185 or 4 miles down from the summit.  The escape ramp is upsloping on the right.  The second runaway truck ramp is about milepost 182, which is 3¼ miles after the first escape ramp, or about 7¼ miles down from the summit.   There are several advisory signs before reaching it and it is an upsloping ramp on the right.  Don't be fooled when the grade eases after the second escape ramp.  It soon goes back to 7% and doesn't bottom out until 2½ miles after the second escape ramp or about milepost 179.

The eastbound descent from the summit of Vail Pass continues almost to the Frisco exit about 11 miles down the hill but the descent is not steady.  There are short steep sections followed by short sections of lesser grade.  The last half of the descent is 3-4% grade.  There are no escape ramps on the east side of the pass.

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