I recently installed some slightly used torsion bars on my 1999 Blazer during the install of a RC 2.5" lift. The bars looked almost new. I never took into thought which was left or right. Does it really matter which side they go in? What are the effects if they were installed incorrectly?
Thanks!

 

Most likely they are different. Torsion bars are computer picked, just prior to vehicle assembly, according to what options the vehicle is equipped with. Your local dealer can give you the part numbers using your VIN. Won't do much good because the part number is not stamped on the bars, and finding new bars is not as easy as it sounds. Worst case scenario, the ride will either be too harsh or too mushy. The important thing is to get front chassis ride height within specs.

 

My torsion bars had the last 3 digits of the part # on the key end side of the bars. Also there too was "R" on right side and "L" on left side bars.

 

I can confirm that I did get the torsion bars in the right sides! Thankfully the stamped #s are on the lower control arm side so it was easy to verify.

 

Now that you say that is there a front and rear of each bar? I think the key end on mine have a lip that stops the bar from sliding back.

 

Yep, there is a left and right AND a front and back. Lipped end goes into the keyed side as you stated