Suggestion:
For Each c In wsSource.Range("H:H")
will check all (million+) cells in H
You might want to find the last row and only do those
Option Explicit
Sub CopyJobs()
Dim i As Long, j As Long, lstRow As Long
Dim wkbkSource As Workbook
Dim wsSource As Worksheet
Dim wkbkTarget As Workbook
Dim wsTarget As Worksheet
Dim sJobNum As String
sJobNum = "Job 160156"
Set wkbkSource = Application.Workbooks("Trucking Jan-Jun.xlsx")
Set wkbkTarget = Workbooks.Open("S:\VT Trucking, LLC\Driver Billing\Trucking 2018\Tracking by Job.xlsm")
Set wsTarget = Sheets(sJobNum)
j = 3
For Each wsSource In wkbkSource.Worksheets
With wsSource
lstRow = .Cells(.Rows.Count, 8).Row
For i = 1 To lstRow
If .Cells(i, 8).Value = sJobNum Then
.Range("A" & i & ":U" & i).Copy wsTarget.Rows(j)
j = j + 1
End If
Next i
End With
Next
End Sub