
At this year’s New Product Symposium, NPS19, Milwaukee finally introduced an M12 version of their Surge hydraulic driver. They say that this is the first 12V-class sub-compact hydraulic driver in the market, and I cannot find any evidence to the contrary.
As a reminder, we attended Milwaukee NPS19 at their expense; our travel, hotel accommodations, and scheduled meals were provided for. In our experience, this is typical practice for hosted media events.
Milwaukee’s M12 Fuel Surge is designed to drive small to medium diameter fasteners and is targeted at maintenance and service workers who work in occupied spaces and cramped locations where a louder driver would be disruptive or require them to wear hearing protection.
Essentially, the M12 Surge will complete most of the tasks you would use a common cordless impact driver for, but it’ll do it without jarring your ears.
The M12 Fuel Surge 1/4″ hex hydraulic driver delivers the same 450 in-lbs of torque as their M18 Fuel Surge driver while maintaining approximately the same length and weight as their M12 Gen 2 impact driver (2553-20).

Milwaukee says the Fluid-Drive hydraulic power train in the M12 Fuel Surge is 2X quieter than competing impact drivers that use a standard hammer and anvil design.
Here’s a quick look at its specs:
- 5.2″ Long
- 450 in-lbs (of longer sustained torque)
- 3,200 RPM
- 3,400 IPM (impacts per minute)
- 4 modes, including a self-tapping screw mode
- LED worklight

Above, you can see the electronic mode selector switch on top of the Surge. Pressing the button in the middle cycles through the four modes. The Rotational direction is controlled by a traditional forward/reverse switch by the trigger.

The M12 Fuel Surge will be available as a bare tool (2551-20) or as a kit (2551-22) including a 2.0 Ah battery, M12 charger, belt clip, and carrying case.
Price: $149 bare tool, $199 kit
ETA: August 2019
Buy Now (Bare Tool via Acme Tools)
Buy Now (Bare Tool via Tool Nut)
Buy Now (Kit via Acme tools)
Buy Now (Kit via Tool Nut)

The M12 Fuel Surge will also be available in an M12 combo kit (2582-22), which includes the M12 Fuel 1/2″ hammer drill, 2.0 Ah battery, 4.0 Ah battery, belt clips for both tools, M12 charger, and contractor bag.
Price: $299
ETA: August 2019
Buy Now (M12 Hammer Drill and Surge Combo Kit via Tool Nut)
Buy Now (M12 Hammer Drill and Surge Combo Kit via Acme Tools)
Discussion
So how does the Surge hydraulic impact driver work you ask? The following Milwaukee M12 Surge promo video explains it. I queued it up to the part where they show how a regular impact driver works, and the Surge’s hydraulic drive mechanism is shown and discussed after that. The whole part is only 30 seconds.
One of the claims that Milwaukee makes about both the M12 and M18 Surge driver is that their hydraulic power train delivers “smooth consistent torque.” This is how they can perform like impact drivers even though their on-paper torque specs are much lower.

Here is a graphic from when the M18 Fuel Surge was first introduced, showing how the M18 Fuel Surge driver delivers lower toque than a standard impact driver but for longer duration. I’d love to see a graph comparing the real-world torque output of a standard impact and the Surge, but that requires a dynamometer and is unfortunately far beyond our testing capabilities.
Milwaukee says that the M12 Surge is 2X quieter than competing impact drivers.
There was a sound level demo at NPS19, but it did not show Milwaukee’s 2X quieter claims, which would correspond to a 10dB difference in noise level.
Our initial reaction was to question the fairness of the test, as the operator did not drive the fastener to the same depth with the M12 Surge as with the competing tool. Following NPS19, we reviewed video coverage of the test and found that this was repeated during 3 separate presentations. We typically advise that media event tests and comparisons be taken with a grain of salt, but in this case we called foul on the demo and have discussed our criticisms with Milwaukee.
In talking to Milwaukee, the 2X quieter claim comes from internal testing that they say is conducted based on UL-certified methods and with specialized equipment.
Still, while we did not see direct proof of their 2X quieter claim, the M12 Surge is undoubtedly quieter than standard impact drivers, just like the M18 Surge.
Once the M12 Surge hits the market we will conduct our own testing to see how much quieter it is compared to standard cordless impact drivers.
I tried the self-tapping screw mode and I still wasn’t comfortable with it after driving a dozen screws. The feedback felt wrong to me. I ended up stripping out at least one screw and not fully driving others. This is probably something that takes a while to get used to.
Stuart’s Note: The same happened to me. In self-tapping screw mode, the M12 Surge stopped itself shortly after tip penetration, and I had to release the trigger and re-engage to fully drive the fastener. The tool might have been a prototype, or test conditions imperfect. We’ll try again once Surge production models start shipping.
Finally, I understand that it’s a cost-saving measure, but I dislike that they include an M12-only charger in these kits. Milwaukee’s M18 cordless power tool kits come with a M12/M18 charger. I suppose it’s fine if you only have a M12 batteries, but I end up donating them to Savers because they are redundant if you have any M18 tools.