When the M12 Fuel Surge came out, we immediately had the question of how it would compare to the standard Milwaukee M12 FUEL impact driver. And, being ourselves, we wanted to see how it compares to other people's 12V impact drivers. This article documents our testing of the Milwaukee M12 FUEL Surge and the M12 FUEL Impact Driver. Go big or go home, right? It's Red vs. Red Pro Tool Reviews head to head!
Check out our best hydraulic impact drivers article to see how these tools stack up.
As always, we'll take a point-by-point look at how these two effects compare, and call out the winner as we go. Remember, everyone has different priorities. One might get more points, but that doesn't mean it's the best impact driver for everyone.
We welcome your constructive comments and let us know why you prefer the Surge or the Standard Shock. Also, keep in mind that while we've invested hundreds of hours collecting face-to-face data, it's impossible for us to test every possible scenario.

Let's meet today's competitors.
On the first corner we have the Milwaukee M12 Fuel Surge
- Model: Milwaukee 2551-20
- Power: Milwaukee M12 battery
- No-load speed: 0 – 3200 RPM
- Maximum Torque: 450 in-lbs
- Impact Rate: 0 – 3400 IPM
Read our Milwaukee M12 Surge Impact Driver Review.
In the red corner, it's the Milwaukee M12 Fuel Impact Driver
- Model: Milwaukee 2553-20
- Power: Milwaukee M12 battery
- No-load speed: 0–3300 RPM
- Maximum Torque: 1300 in-lbs
- Impact rate: 0 – 4000 IPM
Read our Milwaukee 2553-20 review.
The biggest difference between the two tools is that the M12 Surge is hydraulically driven. It uses a hydraulic power system instead of a metal-on-metal impact mechanism. In more traditional terms, we refer to this oil pulse technology as Oil Pulse Technology, and these tools produce significantly less noise and vibration than traditional impact drivers. They also maintain peak torque longer than standard impact drivers due to the longer impact duration.
At 5.2 inches long and 6.8 inches high, Milwaukee's M12 Fuel impact driver is much more compact than previous versions. The Milwaukee M12 Fuel Surge has a big brother in the M18 Fuel Surge, so it's no surprise that its size is a big improvement over the 12V version. It's 5.2 inches by 6.8 inches tall—the exact same footprint as an impact driver.
Measured with a digital caliper, an impact driver technically has a short head of 0.04 inches and is the same height. Essentially, it's a tie.
Verdict: Tie
M12 Surge vs. Fuel Weight
We measured both tools on a digital scale with and without the compact 2.0Ah battery. The Surge's hydraulic drive adds a bit of weight, at 2.00 pounds bare and 2.41 pounds with batteries. The M12 Fuel impact driver is a bit lighter at 1.78 pounds bare and 2.19 pounds with batteries.
While the difference is not huge, impact drivers have an advantage in terms of weight.
Verdict: M12 Fuel Impact Driver
Oil Pulse and Brushless Impact Feature Sets
If you've noticed that these two tools have a lot in common, you'll see this trend continue in their feature sets.
- Motor: Both tools have M12 fuel brushless motors.
- Chuck: Both have one-handed bit insertion but no spring ejection.
- Batteries: Both use M12 stick batteries, which are chunkier than slide-on batteries.
- Speed: Both have 3 speeds and an assist mode, controlled by the same electronic selector on top of the motor.
- LED Light: Both have the same LED light under the clamp.
The only real difference in feature set is the drive system each tool uses. Is this better than that? That's where we're going next!
Verdict: Tie
Surge vs Standard Power
We have two methods for testing the power of an impact driver. In our tightening test, each impact driver tightens a hardened nut to a bolt, and we use a digital torque wrench to measure how much force it takes to break it. This test method will not give the same results as the manufacturer's specification test .
It takes an average of 804 inch-pounds of torque to break the M12 Fuel impact driver's fastening—the best of any 12V impact driver we've tested. The M12 Fuel Surge is introduced and sets a new benchmark at 1026 in-lbs.

Advantage, surge.
In our second test, we verified loading the same hardened nut at specific intervals and seeing how much breaking force (nut breaking torque) each impact driver had.
Here, the M12 Fuel impact driver tops out at 1680 in-lbs (140 ft-lbs), while the Surge tops out at 2400 in-lbs (200 ft-lbs), making a huge difference.
Despite much less torque on paper, the hydraulic drive demonstrates its enduring power with a convincing triumph.
Verdict: M12 Fuel Surge
Compare fastening speed
For fastening speed, we're pushing the limits of what an impact driver can reasonably do before moving to an impact wrench. We used a 1/4" lag screw to test which shock would keep it revs higher.

The M12 Fuel impact driver crushes the entire conventional impact driver field at 397 RPM – more than 100 RPM faster than the closest competitor. The M12 Fuel Surge did well, averaging 346 RPM on the same test, good enough for second place in the 12V class.
Verdict: M12 Fuel Impact Driver
Test fastening efficiency
Tightening efficiency is how we measure the workload of the motor while driving. The closer its RPM is to the no-load speed we tested while tightening, the less stress the motor will experience.

The M12 Surge delivered a solid 11.1 percent efficiency, but less than the impact driver's 12.4 percent.
Note that these percentages are very low, telling us that we are very close to the upper limit of what these impact drivers can handle. If you do a lot of fastening on 1/4" or larger, we recommend upgrading to an 18V impact driver or switching to a 12V impact wrench.
Verdict: M12 Fuel Impact Driver
Milwaukee Surge Noise Reduction

One of the main reasons to consider a hydraulic driver rather than a traditional impact driver is the noise level. The M12 Fuel Impact Driver is at the top of the 12V impact range, producing 100 dB(A) at 24 inches. The M12 Fuel Surge is much quieter than the one we tested at 87 dB(A), or any other 12V model – more than 16 times lower sound pressure level.
Verdict: M12 Fuel Surge
available battery
Apparently, both tools use the same battery, so the same battery can be used. If you are new to the Milwaukee M12 system, here are the options you must use.
- 1.5Ah
- 2.0 ah
- 3.0 ah
- 4.0 ah
- 6.0Ah
Verdict: Tie
Also, the batteries for these tools are compatible with the same tool system. That said, Milwaukee has incredibly deep tools and gear on their M12 system. Whichever effect you choose, it's a huge win.
Verdict: (Obviously) Tie
Milwaukee M12 FUEL Surge and M12 FUEL Impact Driver Prices
You can buy each of these tools, or the tools with batteries and chargers included. However, more 2-tool combo kits sell better than single tools, so we'll consider them as well.
We encourage you to shop around for the best price. We check prices at Acme Tools and Home Depot (Milwaukee doesn't sell them at Lowe's). You might be able to find these on Amazon, but there are currently no authorized Milwaukee dealers there.
Milwaukee M12 fuel surge
- 2551-20 Naked Tool: $149
- 2551-22 kit with two 2.0Ah batteries: $199
- 2582-22 Hammer Drill/Surge Combo with one 2.0Ah battery and one 4.0Ah battery: $299
Milwaukee M12 Fuel Impact Driver
- 2553-20 Naked Tool: $119
- 2553-22 kit with 2.0Ah and 4.0Ah batteries: $169
- 2598-22 Hammer drill/impact driver combo with one 2.0Ah battery and one 4.0Ah battery: $229
With a premium of around $30 for the M12 Fuel Surge, the M12 Fuel impact driver is the less expensive of the two no matter which kit you buy.
Verdict: M12 Fuel Impact Driver
Warranty
Same brand, same quality guarantee. Milwaukee has one of the best companies in the business and they will cover any of them in 5 years.
Verdict: Tie
final verdict
In the Milwaukee M12 Fuel Surge vs. Milwaukee M12 Fuel Surge Pro Tool Thursday review race, the shock riders went 4-2 to 5 draws for the overall win. The two were very close to each other, but despite the scoreline, the two areas won by the Surge could be the turning point in its favor.
If you want the best power and lowest noise of any 12V impact driver, get the Milwaukee M12 Fuel Surge.
If lower price, faster travel and less weight are your priorities, get the Milwaukee M12 Fuel Impact Driver.
Bottom line, both are incredible performers in the 12V class, the correct answer is probably just that you need both!