DEWALT DCG407B: problems, parts and running costs

Checked: 2026-10-17

Summary

The DCG407B is a bare-tool 3.55 lb brushless 4-1/2-in slide-switch angle grinder for DEWALT’s 20V MAX platform, rated at 9,000 RPM and 850 MWO with Kickback Brake and E-Clutch. The friction is mostly about what is not in the box: battery and charger are sold separately, and the tool lacks E-Switch Protection, so a dead battery mid-cut leaves it off until you cycle the switch. Running cost is the battery plus abrasive wheels; the tool is a fair buy near $179 for an existing DEWALT 20V owner and a weak buy above $200.

Common problems and fixes

No E-Switch Protection — if the battery dies mid-cut the tool stays off until the switch is cycled; that no-volt release feature is on the newer DCG413B/DCG416B, not this model. [15]
Battery drain friction across the lineup — Home Depot reviewers of the closely related DCG408B complain the battery drains fast (“could grind one weld tack”) and that a $200 grinder should come with a battery. [13]
The slide switch draws mixed reactions — owners used to paddle switches are split on the slide switch with lock-on; one DCG405B buyer wrote “not sure about the new on/off.” [16]
Retail listings conflate it with the DCG405B — the two are distinct brushless slide-switch 9,000 RPM grinders, but some listings merge them, and one Walmart listing incorrectly claims 13,000 RPM. [9][15]
No independent instrumented test of this exact model — the only hands-on test found was a 30-day deck rebuild with the predecessor DCG405B. [16]

Parts and consumables

Yearly running cost

There is no subscription or fixed service interval; the ongoing cost is the battery and charger (sold separately) plus abrasive wheels, which owners replace as they wear. A DCB205 battery is required for the advertised 56-cut runtime claim. No source gives a per-year total, so the exact yearly figure is not enough data.

When it is a good buy

In-stock US prices observed in October 2026: Toolup $179.00, Shell Lumber $185.30, The Power Tool Store $199.00 and Ohio Power Tool $199.00 (special order) [3][10].
Special-order retailers asked more: Warehouse Supply $213.15, R.P. Lumber $232.09 and The Part Works $276.31 [6][20].
Home Depot Canada listed it at CAD 149 [12]; a Walmart search snippet showed $128 but that listing also incorrectly claims 13,000 RPM [9].
At $179 or below the slide switch, E-Clutch and Kickback Brake make it fair value for a DEWALT 20V owner; above $200 the newer XR paddle-switch DCG413B at $125 tool-only is hard to ignore [3][14].