Verify Door Gauge Rod for Distance Between Guides (DBG) is
Doors require that the "door gauge rod" (for rail
DBG) dimension be 1/8" (3 mm) longer than the dimension
between the base of the throats of the guide shoes. Check
this on two or more door panels. Care in using the door gauge
rod is important because the rails must be set the proper
distance apart and plumb. If you are careful with this procedure,
you will install smooth running doors as the overall side-to-side
play movement (left-right) will be 1/8" (3 mm) as recommended.
On field print labeled DT, read "Gauge Rod" measurement.
Measure actual gauge rod to verify both measurements match.
Also, measure gauge rod against actual door panel shoes.