It was the "base" 2-speed automatic transmission on the small-block Camaros, and very popular. It is a reliable, smooth transmission and capable of very respectable performance. The Powerglide in "built" form was the preferred drag-race transmission for quite a few years, and is still popular for drag racing.
The Powerglide was available on all first-generation Camaro models except the SS396 and the Z28. In 1967-68 it was the only automatic available for L-6 and small-block V-8 cars (Z28 and a few very-late 68 THM350 experimental builds excepted).
2013 MERCEDES BENZ SL-CLASS