The vehicle is replaceable. Standing next to it on I-15 is the part that actually hurts people.
If you are stopped in a travel lane, on a narrow shoulder, or anywhere with traffic passing at highway speed, call 911. Not a tow company, not a referral service, not your insurer. Utah Highway Patrol can close a lane, put a marked vehicle behind you and turn a live hazard into a controlled scene. That is a thing only they can do, and it is free.
If the vehicle still rolls, get it as far right as the shoulder allows, past a curve rather than inside one, and off an on-ramp or bridge deck if there is any choice. If it will not move, leave it. Do not push a car across live lanes and do not stand in a lane to direct traffic.
Turn on the hazards. Then get everyone out on the side away from traffic and move well away from the vehicle — behind a guardrail, up the embankment, or over a wall. A stopped vehicle on a shoulder is struck often enough that sitting inside it is not the safe option people assume it is.
A flat on the driver's side of a freeway shoulder is a tow, not a tire change, no matter how confident you are with a jack. There is no version of kneeling in the gap between your car and a travel lane that is worth it.
Once you are behind something solid, make the call. Have your location ready — the nearest mile marker, exit number or overpass name is far more useful than a dropped pin that lands you on the wrong side of a divided highway. Say whether you are with the vehicle or away from it, because that changes what the operator expects to find.
Get behind a barrier and away from traffic. Then send the vehicle, the drivetrain and the location, and we will match you with an operator.
Get Matched With a Tow OperatorLocation, drivetrain and whether it rolls. That is most of what a dispatcher needs.