Just stumbled across this in a 1953 VARIETY:

<< TOLL THE BELLS FOR poor old Gertrude, a 1918-model Pierce Arrow sedan which had been around the UI lot as long as most of the oldtimers can remember. Lon Chaney had ridden in her for scenes, and so had Norman Kerry and Mary Philbin and other stars of yesteryear. Earliest this week she was run over a cliff on the studio back lot for a sequence In "It Came From Outer Space." Her demlae was not total, however, for before she went over the embankment her motor was removed by a studio mechanic.

And what's left of her now will run the pumps that supply a backlot lake with water. <<

If there's an ounce of truth to this, maybe it's "poor old Gertrude" that we see engulfed in flames, when it's supposed to be Joe Sawyer's telephone truck. I don't remember how much vehicle we see through the flames.

"I've got no problem with going after Tom Weaver ... "