Two problems related to power steering pump have been reported for the 1996 Chevrolet Blazer. The most recently reported issues are listed below.
Certified master auto mechanic, that's why no specific vehicle. Have seen a tremendous amount of these gm trucks, all lines, blaxer, tahoe, k3500, etc. With the belt tensioners coming apart. The center rots out and the spring just makes the tensioner fall sideways. For a while its not bad, the belt is still on and only slips wet. When they come off there is suddenly no power steering, along with of course no alternator. We are changing these at probably one per day, and check all of these vehicles. I have found that all of them with at least thirty thousand miles either need a new tensioner or have already had the tensioner replaced. This covers a few years, from at least 1995 through 1999, and is such a common problem that all the aftermarket suppliers I have seen (gates, napa, carquest) stock these parts. I can tell you the carquest part number, 89231, from memory. As a side issue, you might consider a seperate form for mechanics to fill out, with questions aimed more the information we can provide. After all, we are in the front lines, and can pick up many of these problems more quickly than individual owners probably can.
While driving on the highway there was a loss of power steering due to the power steering pump going out. Dealer replaced steering pump.