Captain Hook is correct about the price tires and the value of a good alignment. I think you can get and alignment for around $80-$100 if all parts are good and its just out of alignment. Other than that if your driving a beater and not to concerned if you mess up already shot tires or good tires for that matter you could align it yourself. With all tires inflated correctly put a straight 2x4 on your front rim and then put a level on that as if your checking plumb on a wall. The 2x4 needs to be placed perfect and is used to extend the level out past the fender. If your camber is good you can wrap a line, the kind used in concrete flat work to level forms, from one front tow hook through the center of tire back through the back of the rear tire to the hitch. do this on both sides and make sure the lines are tight. The blazer needs to be on the ground when making your observations but can be lifted a bit to make your adjustments. With your steering wheel perfectly centered observe the line as it passes over the front tires. If there is a gap at the rear side of the tire and string on the drivers tire with your steering wheel straight, you either always had to hold the steering wheel to the right while driving or the toe is set out on the other side also and would be causing you bump steer and trash your tires. If you adjust your tie rods to bring a small gap between the rear of the tires and the string and the slowly adjust them out so the just push the string out in the same spot until the string is just starting to leave the front of the rear tire. This will give you a slight toe in. Check your steering wheel position constantly and a strap from your steering wheel to your brake can help hold it in line while adjusting. All parts in the front end have to be good to have a good stable alignment. Its possible some moron aligned your front end with a bad idler and that is why it is out with a good one. I have been before said moron before. If you attempt this, I'm not responsible for anything that results.

 

The 2x4 can't be on the tire, only in the rim from inside of lip to inside of lip and not resting on a weight. I have never adjusted camber just checked. I've only done toe and have had good results so far.

 

Thanks for all the help the blazers running good and i tried the alignment trick mentioned i dont have so much play in my wheel now a little bump steering but its drive-able now do you know what that lil foam rubber thing is in between the idler arm and the center link i noticed alot of my front end parts have corroded and torn ones on them