Today, we think of the Blazer -- like the Suburban -- as a badge for a particular vehicle. But, like the Suburban, the Blazer was at one time considered more of a vehicle type than a badge in itself. In this case, it was a pickup truck with a roof over the bed, neatly filling the gap between pickup and the modern SUV. This concept was applied to a few different platforms -- hence, the different lug nut patterns for different Blazer models.
Chevrolet applied the Blazer concept to two different chassis: the full-sized C/K pickup and the smaller S10 chassis, and both came in two- and four-wheel drive. All S10 models used the same 5-475 wheel bolt patterns. However, the four-wheel-drive model used slightly wider rims, with a positive 50 mm offset, to the two-wheel-drive model's negative 11 mm offset. Two-wheel-drive, full-sized Blazers used a garden-variety 5-127 bolt pattern, with a negative 5 mm offset. Four-wheel-drive, full-sized Blazers used bigger axles with heftier wheels; they required six-bolt 6-139 wheels with negative 19 mm offset.
