Dewalt 20V Max XR DCF845 Impact Driver Review

Dewalt DCF845 Angle 5

Quick take

The Dewalt 20V Max XR DCF845 is a standout impact driver capable of breezing through heavy-duty tasks, including driving big structural screws and lag bolts. The three drive modes, combined with the high torque and high impacts per minute, make it versatile for the prosumer at home who desires a high-quality tool or a professional trades worker putting it through the wringer. The DCF845 has fantastic battery run-time performance, is lightweight, and has an extended warranty. However, it’s not without its faults. Some impact drivers are more compact, fitting in tighter spaces, and other models have more drive modes to handle specialty tasks better. It’s also not a great fit for dedicated light-duty jobs where a 12V impact driver is better suited.

Brand Dewalt
Platform 20V Max XR
Motor Brushless
Tested torque in-lbs 612.6
IPM 4,200.0
Drive modes 3
Collet 1/4-inch hex
Same as DCF845B

Global rankings

21 models tested

TestResultRank
Driving speed (sec.)12.82
Torque (in-lbs)612.610
Battery run time (min.)49.05
RPM3,214.07
Bare weight (lbs)2.0311
Impacting noise (dBA)97.412

Editorial opinion

Methodology used: Heavy duty

Editorial rating

4.40 / 5 stars

Pros

  • Excellent battery run time
  • Great torque and driving speed
  • Brushless motor
  • Versatile drive modes
  • Long tool and battery warranty
  • One-handed bit changes

Cons

  • Long collet to back length
  • Not ideal for light-duty tasks

Recommended configuration

DCF845P2

Includes (2) Max XR 20V 5Ah battery

Series lineup

Model #PlatformDrive ModesTorqueIPMReview
DCF84520V Max XR3612.6 in-lbs4,200.0Full review
DCF85020V Atomic3659.4 in-lbs3,800.0Full review
DCF88720V Max XR3880.2 in-lbs3,600.0Full review

Lab results

Torque

Dewalt DCF845 Torquemeter
Dewalt DCF845 Torque Charts

Max torque drive mode 1 (in-lbs): 612.6
Max torque drive mode 2 (in-lbs): 396.6
Max torque drive mode 3 (in-lbs): N/A
Max torque drive mode 4 (in-lbs): N/A

While the DCF845 sped through heavy-duty driving jobs in our tests, the torque output doesn’t explain most of the driving performance. The DCF845 is moderately powerful compared to impact drivers in the Dewalt lineup and outside of it. It is sufficiently powerful to handle demanding tasks, but the Dewalt 20V Max XR DCF887 has a far higher torque output for models in the Dewalt ecosystem.

Compare torque test results

RPM

Dewalt DCF845 RPM Charts

Max RPM drive mode 1 (fwd.): 3,214.0
Max RPM drive mode 2 (fwd.): 2,711.0
Max RPM drive mode 3 (fwd.): 1,437.0
Max RPM drive mode 4 (fwd.): N/A
Max RPM drive mode 1 (rev.): 3,290.0
Max RPM drive mode 2 (rev.): 2,555.0
Max RPM drive mode 3 (rev.): 1,465.0
Max RPM drive mode 4 (rev.): N/A

We appreciate that Dewalt didn’t design the DCF845 with an absurdly high RPM just to impress users with its on-paper performance. RPM does help drive screws fast, but torque does more to explain overall driving performance. An impact driver that ramps immediately to a high RPM results in frequent cam-out and stripping screws.

None of these are issues with the DCF845 with its moderate RPM readouts. There is also no noticeable RPM difference between forward and reverse in all three drive modes. Some Makita impact drivers include specialty driving modes with different forward and reverse RPMs for a given drive setting.

Compare RPM test results

Driving speed

GRK total driving time forward (sec.): 12.8
GRK average driving time forward (sec.): 2.6
GRK total driving time reverse (sec.): 9.0
GRK average driving time reverse (sec.): 1.8

The DCF845 yielded some of the fastest results in our GRK driving speed tests. Dewalt designed the DCF845 with the right balance of features for excellent driving performance without the downsides, such as short battery life, that plague some high-end impact drivers.

The DCF845 is equally capable of driving more than just long GRK screws. We tested driving lag bolts, structural screws, drywall screws, and other standard sizes and lengths. This impact driver handled all with ease for nearly unmatched driving versatility.

Compare driving speed test results

Drive modes

Dewalt DCF845 Drive Modes

Drive modes: 3
Drive mode 1:  High speed 
Drive mode 2:  Medium speed 
Drive mode 3:  Low speed/tightening 
Drive mode 4:  N/A 
Variable speed trigger: Yes

The DCF845 includes the essential drive modes that most users need. There’s a high and low speed impacting mode and a precision driving mode.

The precision mode works well for light-duty tasks, such as general woodworking or driving soft screws in a pinch when your cordless drill is out of reach. But we found ourselves using drive mode 2 more frequently when precision was paramount, such as accurately recessing screws into MDF and drywall studs. The increased driving power is more versatile than what’s offered with the precision drive mode while retaining most of the same accuracy.

Users desiring best-in-class driving versatility should look to a Makita impact driver. The Makita 18V LXT XDT19Z and Makita 40V XGT GDT01Z include similar drive modes as the DCF845 but layer in additional assist modes, including self-tapping and bolt-specific settings.

Collet

Dewalt DCF845 Collet Closeup

Collet size: 1/4-inch hex
Quick-change collet: Yes
Bit-eject collet: Yes
Easy-insert collet: Yes

The DCF845 is excellent for one-handed bit changes. There is an easy-insert feature that doesn’t require sliding the collet forward to accept a bit. A bit-eject feature also lightly ejects the bit when sliding the collet forward.

Dewalt’s collet design is better executed than other brands offering similar features. The easy-insert mechanism is smooth for simple operation, and the bit-eject feature doesn’t jettison the bit too hard to potentially miss catching the bit.

Motor

Motor: Brushless
Impacts per minute: 4,200.0

As should be expected at this price point, the DCF845 includes a brushless motor, which improves longevity, battery efficiency, and driving performance compared to a brushed motor. This motor choice explains some of the impressive battery run time and driving speed performance.

The high advertised 4200.0 impacts per minute also explain the capable driving performance.

Battery run time

Power type: Cordless
Battery run time (min.): 49.0
Battery tested: 20V Max 2Ah (DCB203)
Voltage: 20

The DCF845 is among the best-performing heavy-duty impact drivers we’ve tested, with 49.0 minutes of no-load run time. Adding a 5Ah battery should result in outstanding run time, though we didn’t test the run time with this setup.

We tested battery run time with the 2Ah battery version. With a 20V Max XR 5Ah battery, expect the battery run time to continue outperforming competing models running the same Ah setup.

Compare battery test results

Charging time

Dewalt 20V Fuel Gauge

Charger tested: Dewalt 20V Max (DCB115)
Charging time 2Ah battery (min.): 59.0
Charging time 2.5Ah battery (min.): Not tested
Charging time 4Ah battery (min.): Not tested
Charging time 5Ah battery (min.): 139.0
Charging time per Ah (min.): 28.7
Fuel gauge: On battery

The Dewalt charger that is standard in most kits (model DCB115) isn’t as fast as chargers from other brands. In our tests, it took 59.0 minutes to top off a Max 2Ah battery and 139.0 minutes to charge a Max XR 5Ah battery. Expect that this charger will charge batteries at approximately 28.7 minutes per Ah. Faster chargers charge batteries at 20.0 or fewer minutes per Ah.

Nicely, the DCD112 works with Dewalt’s 12V and 20V platform batteries, conveniently saving space in your shop if you have several tools in the Dewalt ecosystem.

Compare charging test results

Design & ergonomics

Stands upright w/o battery: Yes
Stands upright w/ battery: Yes
Grip material: Rubber overgrip
Magnetic holder: No
Bit holder: No
Belt hook: Yes
Handle angle (deg.): 80.0
Head angle (deg.): 90.0

Weight

Dewalt DCF845 On Scale

Bare weight (lbs): 2.03
Weight w/ 2Ah battery (lbs): 2.83
Weight w/ 2.5Ah battery (lbs):  Not tested
Weight w/ 4Ah battery (lbs):  Not tested
Weight w/ 5Ah battery (lbs): 3.43

The DCF845 isn’t lightweight in its heavy-duty driving class, instead, middle of the pack. The Makita 18V LXT XDT19Z sheds some weight and is a better option if you covet a light, equally powerful setup.

The working weight can differ significantly depending on the battery run in your setup. To keep it as lightweight as possible, We recommend combining the DCF845 with Dewalt’s new 20V Powerstack 1.7Ah battery, which weighs less, has a smaller footprint, and performs better than Dewalt’s 20V Max 2Ah battery, which is a solid alternative for a svelte setup.

If weight is less of a concern, pair the DCF845 with Dewalt’s 20V Max XR 5Ah battery for a longer run time and improved driving performance. Moreover, this setup is one of the lightest 5Ah kits we’ve come across.

Compare weight test results

Footprint

Dewalt DCF845 Footprint1
Dewalt DCF845 Footprint2

Max height (bare tool, in.): 7.375
Max width (bare tool, in.): 3.000
Collet to back length (in.): 5.125
Base length (bare tool, in.): 3.500
Base width (bare tool, in.): 3.000
Trigger circumference (in.): 6.750
Handle circumference (in.): 5.125

The DCF845 has a narrow profile but isn’t highly compact like the Dewalt 20V Atomic DCF850, which has a far shorter collet-to-back length. Held in hand, the DCF845 still feels nimble compared to some of its competition.

Compare footprint test results

Driving clearance

Min. interior width clearance (in.): 7.750
Min. top edge clearance (in.): 1.250
Min. interior 45-deg. clearance (in.): 6.500

While the DCF845 casts a thin shadow viewed from the front, it didn’t shine in our interior clearance tests, which is somewhat expected for a heavier-duty impact driver. The primary reason is the long collet-to-back length. Otherwise, the footprint resembles many competing impact drivers with similar average results in our clearance tests.

Compare driving clearance test results

Noise

DCF845 Impact Driver Noise Chart

Max noise no load (dBA): 78.8
Max impacting noise (dBA): 97.4

No impact driver whispers while impacting, including the DCF845, a moderately loud impact driver that can damage your ears with prolonged exposure. You can shave off a few decibels of impact noise performance with the Milwaukee M18 Fuel 2953-20, but you’ll need to switch up impact driver classes to markedly improved noise performance.

The Milwaukee M12 Fuel Surge 2551-20 and Milwaukee M18 Fuel Surge 2760-20 are hydraulic impact drivers with more subtle impacts, albeit lower torque.

Compare noise test results

Vibration

Max head vibration no load (m/s2): 32.9
Max grip vibration no load (m/s2): 2.9

Compare vibration test results

Light

Dewalt DCF845 Light
Dewalt DCF845 Light Closeup

Light: Yes
Light on/off: No
Number of lights: 3
Light time delay (sec.): 20.0

The DCF845’s work light illuminates a moderately large and bright surface area that is focused in the correct location. One minor head-scratcher is Dewalt’s choice of a 20-second time delay for the light, which is unnecessarily long and drains battery life.

There is no dedicated flashlight mode, one featured included with some Makita impact drivers, where the trigger acts as an on/off button to turn on the light without moving the motor. You also can’t disable the light.

Warranty

Tool warranty (years): 3
Battery warranty (years): 3

Dewalt stands behind the durability of its impact drivers with exceptionally-long warranties. The DCF845 has a three-year warranty. Dewalt 20V batteries include a two-year warranty.

Dewalt also offers free maintenance and replacement of worn parts for one year for the DCF845 and three years for its 20V batteries.

Picture of Nathan Hamilton
Nathan Hamilton
Nathan Hamilton is the founder of DIY Gear Reviews and a recognized expert in the home and DIY space. He has over 200 bylines covering topics such as power tools, hand tools, and woodworking. Nathan is the strategic director for DIY Gear Reviews, deciding everything from the content covered to designing the testing methodologies for lab-tested reviews. He can be emailed at nhamilton@diygearreviews.com.

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