Clamshell Strut Spring Compressor - 6494

The OTC-6494 is top quality, well designed, and very safe to use. The OTC tool was used to replace the Bilstein front shocks on E28 BMW M5. (The E28 springs have seven coils; coils are approximately 14mm in wire diameter, coil itself is about 5.75 inch in outer diameter.) By working the OTC-6494 around the spiral shape of the coil spring (a key step), I was able to engage five coils out of the total of seven, relatively easily. With five coils engaged, the spring compresses evenly with minimal effort (requires less than 30 ft-lb of torque on actuating screw), allowing for removal of the upper strut bearing and disassembly of suspension strut with ease. Note: OTC-6494 spec: springs of 4-9" OD, with wire diameters of 7/16 to11/16”. I’ve been repairing cars and trucks over 65 years, this is a good tool.

Worked like a charm! I've changed many strut springs over the years using the old school manual spring compressors. Never had a failure but they bent at what I thought was some extreme angles during use. Not ready to drop almost a grand on a shop-grade strut compressor, I tried this one for what appeared to be a slightly safer design. In actual use, it does feel safer. Of course you have to use caution with any such device. But anyway, it compressed the spring with ease. The large threaded rod did bend even with the mid sized Toyota 4Runner springs, but not to the extreme that lesser spring compressors would. In use, you have to "finesse" the hooks into the coil springs, both top and bottom. And due to the simple design of a circular coil spring, the hooks will never be 100% completely even around the coils. So it's expected to have some unevenness in the device and slight bending of the rod when the spring is being compressed. Remember to compress only enough to be able to loosen the top nut (no need to attempt to over compress the coils). In closing, be sure to wear safety glasses and in my case, I used some high temperature brake grease on the threaded rod and an air impact wrench which made quick work of the actual compressing procedure. In a few hours, I had fully did both front struts on my rig. And that was taking my sweet time to clean and inspect the various suspension components for damage, wear, etc.

This tool was very easy to use and very sturdy, well made. I would highly recommend it. There is a version of this tool at Harbor Freight from Maddox that costs a lot less but you can't go wrong with the quality of OTC when it comes to handling strut springs.

I bought this on the recommendation of a Honda group I am a member of. I have used many spring compressors over the years and this is the safest and easiest to use of any I have ever bought. Was well worth the money. In the past with my Element, I have bought the full assembled shock assemblies from Honda. Since the element is getting older, Honda has decided to stop making the complete assemblies. I reluctantly ordered the individual replacement parts along with this spring compressor. I f I had know how well this worked, I would have ordered this years ago. EDIT: Now used it for my 2018 F-150. Worked perfectly on the larger springs...A++++

Compressing the springs was the one thing that made me nervous about replacing the 10-year-old shocks on my 2004 Toyota Prius. But saving over $1000 was stronger motivation, so I decided to get this spring compressor to solve the safety issue. First, let me mention that I've read people say you can take your removed shocks with springs to a mechanic and get the pair swapped for around $30. If you have a second vehicle or a friend willing to take you and an inexpensive mechanic you trust, that might be a better option than buying this expensive compressor. But if you plan to use it on many vehicles throughout your life, it will eventually save you money and time. Some auto parts places also rent them for a deposit and give you back the full deposit upon return, but I feel like there's some risk there using tools previously used by random people that may have overstressed them. Based on what I've read, the spring compressors that use two separate bars are not very safe. Even with locking pins, the unconnected bars can slide around the spring, allowing it to expand on one side with a sudden force that can injure if body parts are near the spring or slipped bar, or in the middle of screwing on one or the other bar. I suppose it's pretty unlikely that you'll be hit as long as you're careful, but mistakes happen, and there's always the risk of damage to whatever the springs are sitting on. I found a reviewer mention using 3 bars instead of 2 is more safe, but that strikes me as easily creating an unbalanced force that would be more likely to make two of the bars slide towards the third. If you're thinking of doing that, at least do some extra research to make sure that adds to the safety instead of making things worse. Nobody sells sets of 3 bars that I've seen, and there's likely a reason for that. If you read my update near the end, I've changed my mind and think the 2-bar compressors are actually more appropriate for light sedan car springs, especially front springs. I did use this clamshell compressor on my front springs but it was very difficult. Read the full review for details. The OTC clamshell compressor is heavy and all the parts and welds look solid. Using it to compress a spring is a breeze and being able to use an impact wrench is a great bonus. I used it on light car springs so I can't comment on how it handles heavier springs, but it did a great job for me and I confirmed with a torque wrench that I wasn't pushing it anywhere near its limits. I did notice the springs slipped slightly in the jaws a couple times as I was moving the contraption all around trying to verify the ends of the new strut were positioned identically on the spring as compared to the old strut. Seeing that slipping, I was glad I wasn't using the two separated bar compressors. The compressor itself also provides a safe thing to hold and move around without getting your fingers near the spring. Technically the manual says you're supposed to clamp the OTC in a vice, and I can see that being even safer and making slipping much less likely, but the one vice I own would not do well to hold the recommended round top bar on the OTC and I figured that risking it falling out of the vice and the spring breaking as it hit the ground was more dangerous than skipping the vice. One annoying thing is the manual says you need to clamp at least 4 loops of spring or the unclamped loops will expand and keep too much pressure to remove the strut. Yeah, you can keep cranking the OTC smaller but at some point you're putting too much pressure on the 2 or 3 spring coils you've got clamped and you're risking breakage. One reviewer said they couldn't even get the OTC small enough to release the pressure on the ends of the shock. So they sell the OTC 6583 Bridge Accessory to sit over the end nut on the shock and the bridge provides two bars you can clamp two of the OTC hooks onto. That's great, but charging over $50 for that small accessory is rather ridiculous. Unfortunately, if you have a small car with short front springs, you're stuck with paying it if you want to maintain the safety you're trying to get from using this style of spring compressor. UPDATE: I got the front shocks done with the bridge accessory, but it was far from ideal. Here's my notes about it: When I took the spring off the old front right strut, I put the bridge accessory on the top of the strut as the manual said to do (it also said NOT to put it on the bottom plate of the strut but did not say why). This caused the top half of the “top hat” to cant to the side quite a bit despite having the shock between the two halves of the top hat to keep them aligned. Once I removed the bolt on the end of the shock, I was afraid something might spring apart once the shock retreated from the two tophat halves so I loosened it from as great a distance as I could sit. Oddly the shock did not retreat much and I found that the top of the tophat came loose but the bottom remained wedged on the strut at an angle, preventing the spring from decompressing. I had to hit it with a rubber mallet and suddenly the spring pushed it off. Not with much force, luckily - it only fell a couple inches away. When it came time to compress the spring for the new strut, I knew I would have no chance of getting the strut rod through the two halves of the tophat if I put the bridge accessory on the tophat to compress the spring, so I had to put it on the bottom plate. I first set the bottom of the spring in the correct orientation on the bottom plate against the rubber and used a big binder clip to hold it in place. Then you need to orient the bottom of the top hat to match the rotation of the bottom plate (see instructions for your car) which I did, clipped it, and marked the bottom of the top hat as well as the rubber with a silver pen. I then unclipped and removed the top hat. I sized the bridge as small as possible after putting it around the bottom of the strut. I managed to remove one side of the bridge to put it on instead of releasing the bridge from the strut tamer jaws but it was hard to get the side of the bridge to fit back on (again it required twisting the arms of the strut tamer). The pins on the bridge got very much in the way and would only fit when turned to a very specific angle with their rings pointing out from the strut and down towards its bottom. The flat side of all pins were also toward the bottom of the strut (I think). One of the two tips of each pin was scraping into the side of the bridge. When I compressed the spring it pulled the end of the strut rod towards one side of the spring, leaving too little room to orient the bottom of the top hat correctly. I decompressed and rotated the strut about ' turn and compressed again. I should have rotated another ' turn but I got things to barely fit and put the nut on the end of the strut rod about halfway or more. As I loosened the compressor I found I could still turn the bottom of the top hat against the spring for a little bit and I used a rubber mallet to shift things a little closer to where they should be. I kept pulling the rubber so the mark matched the end of the spring and turned the bottom plate so the tab in the rubber was centered in the notch in the bottom plate. As I released the spring too far, I could no longer turn or shift anything. Things were rotated correctly but the spring was about ¼” off center. I think small misalignments correct themselves once the car bounces awhile and I haven't had any obvious problems in the last year of driving. Due to the difficulty of using this compressor on small front-end shocks I actually think it might be safer (and certainly easier) to use the cheaper set of two compressor rods where you can independently adjust their lengths to pull the spring into the correct alignment to align the tophat. It doesn't seem like the forces involved in these smaller sedan springs are that extreme since I never had anything shift violently or send a part flying, plus I watched a video where a guy actually had enough body strength to compress a sedan spring (Miata, I think) and get the top had on without a compressor. The 6583 Bridge Accessory is technically made for the larger Strut Tamer compressor, but OTC tech support says it can also be used with this clamshell compressor. If you read through the product questions about this compressor, you'll find someone say that's true, but its bars are too large for this clamshell to hold with the locking pins in place. That's ridiculous because OTC no longer makes the original bridge designed for use with this compressor, but we'll see what happens when my bridge accessory arrives. My one complaint with product quality is the big screw used in the center had a couple of tiny impact dents in it that prevented it from screwing in past the dents. I filed at them with a metal file for a couple minutes and that solved the problem. The manual says the screw should also be lubricated, so I used Mobil MOBIL 1 GREASE Automotive Grease which I had bought for the front shocks anyway. Still, it would have been nice if the product listing mentioned it needing lubrication. If you have a light car, you also might get away with this cheap compressor for about $60. I didn't want to risk it since it has only two reviews, and I think it's the same model sold by Harbor Freight which I've read a couple of bad reviews on, but I've also read a few good reviews of people who were surprised by that compressor's quality, so I'm not sure. The product description says its screw is limited to 15ftlb which is half of what the OTC's screw is rated for, so I expect the OTC is built about twice as strong. The cheap compressor also comes with a ring that looks similar to the OTC bridge accessory, but I looked up a manual for one of those compressors and it calls that ring a "safety ring" and says to slip it over two of the claws and that "The Safety Ring (19) will keep the claws from springing open and causing injury". Since it wouldn't stop the other pair of claws from springing open I'm not quite sure how it helps but I guess it would put some limit on how far the other set of claws spring open. The fact the cheap compressor comes with the added safety ring also begs the question - do they think the jaws are likely to break open? Either way, I don't think the ring is meant to be used like the OTC bridge accessory, which means the cheap compressor can't be used on most short springs. I've read a couple people say they tried to use clamshell compressors without a bridge accessory and you end up having to try to compress 3 coils on one side and 2 coils on the other side and the tool isn't designed to deform itself far enough to make that possible.

This spring compressor makes changing struts allot faster and much safer then the lighter rental tools out there. clamped it on and ran it down with the impact, its that easy.

Shipping was fast. Tool performed as expected.

Excellent purchase

Used it on my 2008 lucerne worked good, felt safe when compressing strut

Thank You