New for 1975 was a catalytic converter. This was also the first model year to feature GM's new HEI electronic ignition, replacing the old points-style ignition from years previous.

Also new cosmetically for the '75 Blazer (and also C/K pickup trucks) was a redesigned front grille with larger rectangular grille openings. Also, the recessed areas of the headlamp trim were painted silver instead of black. These changes would follow through the 1976 model year.

1975 was also the first year for the factory-installed roll bar just behind the front seats.

The base engine remained a 250-ci I6 rated at 105 horsepower at 3800 rpm. Optional engines included a 350-ci V8 rated at 160 horsepower, and a 400-ci V8 rated at 175 horsepower.

The 1975 Blazer was the last Blazer to feature the full convertible top. When restoring a 1975 Blazer, the fiberglass top can be replaced with a removable canvas top if so desired.