i have 1999 chevy blazer 2 wheel drive when i back up out of parking spot makes popping sound.and has play in steering wheel when driving.i lifted the front end off ground and all the steering connections move.

 

sounds like you may have a bad wheel bearing, possibly a ball joint

 

Lift the car up on jackstands and shake the wheel to see if you have any play. Grab it at the 12 and 6 o'clock position if you feel some movement it's indicative of worn ball joint. Grab at 3 and 9 o'clock if there is play it may be your wheel bearings. These are general guidelines and do not always work but either way there should be no play in the wheel. Grab it and SHAKE IT LIKE IT'S HOT!

 

The play in the steering wheel is most likely your steering box, they get worn out. IMO, do not bother with a reguild kit, way too much to screw up and a bazzillion little things to replace. Rock Auto parts has the units for around 150 I believe.

The " popping " sound is most likely your upper control arm bushings starting to shred.wear etc. I had the same exact thing. Back out of driveway, hear popping sound, start forward, hear smaller popping sound. Ball joints were tight as hell with 134 K on it but the rubber bushings looked cracked and old. I replaced both upper control arms, with Moog ball joints 96$ each for complete A arm and Ball Joints and bushings and it went away.