Just used this on a 2009 Silverado 1500 to replace shock absorbers. Short test - works perfectly. Longer Version - These two-piece devices are damn questionable to use, the nature of the design will only result in misalignment and eventual fly-out of the rods from the compressed spring. Realizing this, I took extra precautions to use them safely. Once you get them, clean them, grease the threads and twist them a couple of times. This will get rid of any imperfections so they work smoothly. The last thing you need is to tie off a thread so you think it's tight, then pull the other side too tight and boom, you're dodging the metal rod that's detached from the spring. I did this procedure and it worked fine and smoothly. Make sure you place them exactly opposite each other on the spools, ie 9 and 3, 12 and 6, however you hold the rack to get the job done. Tighten SMOOTHLY and EVENLY without using an impact wrench/drill/anything with a motor. I secured them and made 4 or 5 turns of the ratchet on each side to get the spring compressing well and evenly. They felt the same when I tightened them, no stickiness nothing to say but smooth operation. To be on the safe side, I put the stand on the floor, put the 2x6 on it, knelt on the 2x6 and ratcheted it up with one hand. and the other holds the spring compression grip. I also had a heavy blanket on the back of the counter so I wouldn't hit my head if something went wrong. You only need to compress the spring just enough to leave a small gap for the strut's cylinder. off, nothing more. Don't try to compress the spring, it would probably be a disaster if you succeeded. I used a large screwdriver to check the play on the top of the strut, once I had it I removed the bolt, pulled the shock out, moved everything to the new shock and put it back in place, no fuss. .When loosening a compressed spring, do the same, SMOOTHLY and SLOWLY. It's not a race, it comes off well if you lubricate the threads. I've only used this on a Silverado 1500, the truck springs are massive and they did a great job with hand tools. If you're using them in a small vehicle, the same should work for you. It's safest to take the parts to a shop with the right compressor and have a professional do it, but if you choose to be a professional driveway mechanic, do it safely and understand what you're messing with. The product does a great job, probably about double the rental models you can get at your local auto parts store, and feels sturdy. There's no physical screw to hold the clips to the spring coils like other models, but the built-in hook extends far enough that the coil won't slip if you use it properly.