Re: Rock truck question
			 
			 
			
		
		
		
			
			Down my way - Kentucky & southern Indiana - they are called rock knockers.  To prevent tire punctures, some quarries use large chains instead.  They are looped below the wheel, between the tires with the two ends pinned to the underside of the bed.  Also, some of the solid knockers have a football-shaped end welded on, giving a rounded surface that reduces damage the sidewall. 
 
Ken
		 
		
		
		
		
		
		
			
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				Big iron is awesome!
			 
		
		
		
		
		
	
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