I got this information from Jolly's Site.

1960-62:
Torsion Bar Front, Most all Models
Coil Spring Trailing Arm Rear - 1000, 1500
Leaf Spring Rear - 2500 & Larger

1963-66:
Coil Spring Front, 1000, 1500 & 2500
I-Beam Front Axle - 3500 & Larger
Leaf Spring Rear - All Models
Some Larger Trucks had Air Ride Springs

1960 GMC 305A V-6 Gallery Page
Remember, the government cannot give --anything to anyone --that they have not first taken away from someone else.
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