Moving from an impact driver to an impact wrench is more than just changing the bit retainer to a socket adapter. It means youโre moving way up in power and to a completely different set of applications. Impact wrenches are common around auto shops thanks to the intense metal to metal connections they often secure. Youโll also find them on industrial and commercial jobsites where they make a living around steel frame structures.
The Metabo SSW 18 LTX 400 BL Impact Wrench is in the middle of the power range of impact wrenches. On paper, itโs right where it should be for compact impact wrenches. Itsย 295 foot pounds of torque make it a versatile tool that can handle your light and medium dutyย metal applications while moving into screw driving applications with a simple adapter. In fact, Metaboโs official title of this impact wrench is an impact screwdriver according to their website.
My first thought? Well, 295 foot pounds is 3,540 inch pounds of torque โ way too much for screw driving! Metabo has brought theย old idea of a multi-speed driver around to a new and compelling innovation โ the 12 speed impact wrench. I brought the idea up to a few other guys from the PTR team, and it seems Iโm not the only skeptic in the group. Weโre going to take a closer look at how the Metabo SSW 18 LXT 400 BL Impact Wrench is dialed in.
Metabo SSW 18 LTX 400 BL Impact Wrench Specifications
- Power Source: Metabo 18V Lithium-Ion Battery (tested with 3.1ย amp hour LiHD)
- No Load Speed: 0 โ 2150 RPM
- Torque: 295 Foot Pounds (3,540 inch pounds)
- Maximum Impact Rate: 4,250 IPM
- Weight: 4.2 Pounds (including battery)
- Bit Retainer: 1/2โณ Square
- Included in Kit: Impact Wrench, (2) 3.1ย Amp Hour LiHD Batteries, Belt Hook, Case
- Online Price: $399ย (5.5 amp hour LiHD kit),ย ย $329ย (3.1 amp hour LiHD kit), $319 (bare tool)
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Metabo SSW 18 LTX 400 BL First Impresssions
Ergonomics
The Metabo SSW 18 LTX 400 BL Impact Wrench has a footprint in between an impact driver and a drill. Itโs clearly smaller than the high torque impact drivers out there while still coming in under the length of a standard 18V drill. You are looking at a much more powerful tool than an impact driver, so the weight is higher at 4.2 pounds with the battery. Itโs not the lightest of the compact impact wrenches, but itโs way under the high torque models.
Balance on the Metabo Impact Wrench is good with a slight forward lean when gripped. With the 3.1 amp hour LiHD battery, the weight and balance didnโt fight against me on overhead applications. I have a medium sized hand and I found the handle to be on the large size for me. Itโs not an issue when it comes to grip, I just prefer a thinner handle.
Everyone that Iโve had try this model have taken a minute to figure out the battery eject. The lock is on the tool rather than the battery.ย I have found that using the heel of myย hand to press against it is the easiest way to get the batteryย out.
Metabo SSW 18 LTX 400 BL Impact Wrench โ 12 Speeds?
Letโs talk about those 12 speeds for a minute. With brushed motors, you actually needs a physical gear box to have multiple speeds. With brushless, however, electronic controls are already built into the system โ creating multiple speed settings isnโt a big deal.
We know at top speed, weโre going to get 2,150 RPMs, 3,450 inch pounds of torque, and and 4,250 IPM. Is the lowest speed low enough for fastening duties though? Weโre going to see 590 RPM, 1,151 inch pounds of torque, and just 1,200 IPM in mode 1. Soโฆ yes, Iโll give that a cautious voteย for fastening. Iโll give a more confident vote for the fact that we get 12 separate speed/torque settings for applications that require more precision.
Just as a comparison, my 12V impact driver puts out 2,000 RPM, 1,100 inch pounds of torque, and 3,000 IPM. Metabo definitely has the torque in Mode 1, but the RPMs and IPMs are significantly lower, so weโll have to see what happens.
Metabo LiHD Battery Technology

Weโve already gone into some detail about Metaboโs new LiHD battery technology. By creating a higher density lithium-ion cell, Metabo is claiming 67% greater power and 87% more run time than traditional lithium-ion batteries. Itโs a bold claim that is game changing. In speaking to the Metabo crew at STAFDA this year, they explained that simply changing the battery changes the tool.
In the case of theย Metabo SSW 18 LXT 400 BL Impact Wrench, LiHD batteries took the torque rating from 295 foot pounds to 325. While not exactly a 67% increase (itโs actually only 10%), that doesnโt take into account run time and speed, much less the actual speed of performance. Thereโs clearly something magical going on inside that battery pack, and itโs changing the playing field for Metabo.
Metabo SSW 18 LTX 400 BL Performance
Weโre tool junkies. That means that weโve got impact drivers for screw driving and impact wrenches for socket applications. We just donโt do a whole lot of crossover. The idea of taking the power of an impact wrench and giving enough versatility to replace an impact driver is pretty forward thinking. Thatโs what we decided to do โ try it on the same socket applications we expect it to perform well in and try to drive screws with the control we expect from an impact driver.

Lug nuts and lag bolts are really no challenge for the Metabo SSW 18 LTX 400 BL Impact Wrench. This is expectedย as you really need justย 200 foot pounds of torque to handle lug nuts. Since most impact drivers can handle lag bolts with reasonable results, it should be no surprise that Metaboโs impact wrench can drive 1/2โณ x 6โณ lags with relative ease. Hereโs the thingโhaving 12 speeds allows you to dial in a wider variety of specific torques that gives you consistent results every time in these high stress applications.
The question we were all curious about was in the ability to drive screws. We picked up a 1/2โณ square to 1/4โณ hex adapter at Loweโs. There were plenty in stock, so finding one shouldnโt be an issue. Figuring low speed was the place to start, there was plenty of control and torque to sink a 3โณ screw into pine with no problem. It was actually a little on the slow side, though the impact mechanism didnโt have to kick in until it was halfway through the drive.
With a little experimenting, I found that Mode 5 matched the driving speed of my go-to Ridgid 18V impact driver. I thought the trade-off would be control. That didnโt turn out to be the case. The trade-off isย compactness. Using an adapter adds another 1-3/8โณ to the 6-1/2โณ youโve already got. What you gain in versatility is worth it if youโre not constantly working in tight spaces.
Another subtle performance effect I noticed was a slight soft start. Normally, youโll feel an impact tool pull to the side if you just hold it up and start it. The soft start on the Metabo SSW 18 LTX 400 BL Impact Wrench creates even greater control when starting to drive a screw.
Editorโs Note on Torque and Speed:ย Yourย tightening torque depends on the impact duration. With an impact duration of approximately 5 seconds, youโll reach theย maximum tightening torqueย at any of the 12 speeds/modes. With that said,ย the torque curve depends on the type of application. Hereโs a quick guide of how this works (image courtesy of Metabo):
With a hard screwdriving application (screw couplings in hard material such as metal), maximum tightening torque is already reached after a short impact duration (See figure a).ย With a soft screwdriving application, howeverย (driving inย soft material likeย wood), a longer impact duration is required (See figure b). Metaboโs generalย recommendationย is to simplyย determine the correct impact duration by carrying out trial screw driving. Because speed affects torque, and applications are infinite, thereโs no real effective way to tell you what each of the 12 torque/speed levels will doย in a way thatโs practical.
Conclusions
Metabo has taken a tool that fell in between a high torque impact wrench and an impact driver and created a more versatile option. By giving the Metabo SSW 18 LTX 400 BL 12 speeds, it brings almost all of the 18V impact driver applications into its fold. For the professional working in industrial and commercial applications, this is an impact wrench that replaces the need for an impact driver by just adding a $7 adapter. Even residential construction pros will enjoy the combination of applications you can tackle.
For a guy that could carry both tools, Iโd rather not if I can help it. Whenย compact work is required, I can turn to my 12V kit to reach the areas this model canโt. Iโd recommend this for any professional that frequently turns to a blend of compactย impact wrenches and full size impact drivers to get the job done. This is just based on how we were able to test it. In addition to auto shops, Metabo also recommends this for shipyard use and anywhere else that requires specific torque settings and repeatable results.



