Yes, if you are NOT a W2 employee, then you can count all of your miles from the time you leave your office until you come back to your office as long as they are not reimbursed and only business miles.
If you are a W2 employee, then these expenses are no longer deductible under the new tax laws.
"You can no longer claim any miscellaneous itemized deductions that are subject to the 2% of adjusted gross income limitation, including unreimbursed employee expenses."https://www.irs.gov/publications/p529