Which Cordless Grease Gun Clears Rusted Fittings Fastest?
Most owners should pick the Milwaukee M18 2646-20 for its 10,000 PSI rating and shared M18 battery platform. Fleet techs greasing heavy equipment daily get more from the Lincoln Lubrication 1264 PowerLuber. DeWalt 20V MAX owners can match that pressure with the DEWALT DCGG571M1 kit instead.
Most home and shop buyers land on the Milwaukee M18 2646-20, since its 10,000 PSI rating clears fittings that lower rated guns cannot budge. It shares batteries with the wider M18 lineup, so an existing charger often covers it. The tool ships bare, meaning a battery and charger add extra cost if none are already on hand. Techs greasing heavy equipment all day may still prefer the raw pump durability of the Lincoln Lubrication 1264 PowerLuber.
Cordless grease guns differ more in real world torque than their PSI ratings suggest, and a gun that stalls on a rusted zerk fitting is dead weight on a truck. We compared rated pressure, battery platform, cartridge versus bulk loading and owner reports on jamming and runtime across seven current models.
The shortlist, ranked
Milwaukee M18 2646-20 Cordless Grease Gun
This M18 platform gun is rated for 10,000 PSI, enough to clear fittings that stall lower powered guns. It ships as a bare tool, so a compatible M18 battery and charger are needed separately. Owners already holding other M18 tools call this the simplest add to their lineup, since no extra charger lands on the bench.
Pros
- Rated 10,000 PSI clears stubborn or rusted fittings
- Shares batteries with the broader M18 tool lineup
- Accepts cartridges or bulk fill loading
Cons
- Sold as a bare tool, battery and charger cost extra
- Heavier than the compact 12V options in this group
Lincoln Lubrication 1264 PowerLuber 20V Cordless Grease Gun
Lincoln built its name on fleet grade lube equipment, and the PowerLuber 1264 carries that reputation into a cordless body. Its 20V pack and pump target daily heavy equipment service rather than occasional home use. Techs servicing trailers and farm machinery report the pump holds up under repeated bulk fill loading better than lighter duty guns.
Pros
- Purpose built for daily fleet and heavy equipment service
- Handles repeated bulk fill loading without losing output
- Strong reputation for long term pump durability
Cons
- Uses a Lincoln proprietary battery, not shared across brands
- Costs more than general purpose cordless guns in this group
DEWALT DCGG571M1 20V MAX Cordless Grease Gun Kit
This kit bundles a 20V MAX 4.0Ah battery and charger, so it runs straight out of the box. Rated pressure matches the Milwaukee at 10,000 PSI. A built in pressure relief valve protects the pump when a fitting stays blocked, according to the listing.
Pros
- Kit includes battery and charger, ready to use immediately
- Matches the 10,000 PSI rating of the top pick
- Pressure relief valve guards the pump against blocked fittings
Cons
- Mainly a platform starter without other 20V MAX tools on hand
- Bulkier than the Ryobi and Performance Tool models here
Ryobi P620 18V ONE+ Cordless Grease Gun
Ryobi’s 18V ONE+ platform spans well over 280 tools, so this gun slots into a battery collection many DIYers already own. Rated pressure trails the top two picks at 7,500 PSI, plenty for routine truck and mower work. An LED work light helps in dim engine bays, a detail owners mention often.
Pros
- Fits an already large 18V ONE+ battery collection
- LED work light aids visibility in tight bays
- Lighter than most 20V competitors in this group
Cons
- Sold as a bare tool without a battery included
- 7,500 PSI trails the highest rated guns here
WORKPRO 20V Cordless Grease Gun Kit
This kit bundles a 20V battery, charger, carrying case and extension hose, covering everything needed for a first cordless grease gun. Rated pressure sits at 4,500 PSI, enough for routine maintenance rather than packed fittings. First time buyers cite the complete kit as the reason to skip a bare tool purchase.
Pros
- Complete kit with battery, charger and case included
- Extension hose reaches awkward or hard to angle fittings
- Lower upfront cost than the platform tools here
Cons
- 4,500 PSI struggles on old or badly packed fittings
- Battery platform is not shared with major tool brands
Craftsman CMCE521B V20 Cordless Grease Gun
Craftsman’s V20 platform keeps this gun affordable for anyone already holding V20 batteries from yard or shop tools. Rated 6,000 PSI covers most passenger vehicle and small equipment fittings. Owners describe it as a straightforward, no frills gun built for occasional use rather than daily fleet work.
Pros
- Lowest cost option among the platform tools here
- 6,000 PSI covers most routine service fittings
- Compatible with the wider V20 tool lineup
Cons
- Sold as a bare tool, needs a V20 battery on hand
- Not built for constant daily heavy equipment use
Performance Tool W50065 12V Cordless Grease Gun
At roughly 13 inches, this is the most compact gun in the group, built to reach fittings buried in tight engine bays or undercarriage work. Its 12V battery and charger come included, so it runs straight out of the box. Rated 4,500 PSI handles routine fittings but not anything badly packed or rusted.
Pros
- Compact size reaches tight engine bay and undercarriage fittings
- Battery and charger included in the box
- Lighter than the full size 20V guns here
Cons
- 4,500 PSI is the lowest rating in this group
- 12V pack empties faster than 20V options under heavy use
What matters most
What separates a good cordless grease gun from a bad one Rated pressure, battery platform and cartridge handling separate these guns more than any feature list. A pump stuck at 4,500 PSI struggles on old, packed wheel bearing fittings that a 10,000 PSI unit clears in seconds. Flow rate decides how fast a full point of grease actually gets delivered, not just whether the trigger pulls. Battery platform decides whether the tool adds another charger to the bench or slots into gear already owned.
How much PSI do stubborn fittings actually need Most passenger vehicle fittings accept grease under 3,000 PSI without complaint. Farm equipment, older trailers and gear left outside for years can pack solid and resist well past 6,000 PSI. Guns rated at 10,000 PSI, like the Milwaukee M18 2646-20 or DEWALT DCGG571M1, give headroom for those worst case fittings. Routine truck and mower maintenance rarely needs more than 4,500 to 6,000 PSI.
Does battery platform matter more than the gun itself A bare tool grease gun costs less upfront but only pays off with a compatible battery already sitting in a charger somewhere. Milwaukee M18, DeWalt 20V MAX and Ryobi 18V ONE+ each cover hundreds of other tools, so the gun becomes one more accessory rather than a standalone purchase. Starting from zero, a kit with an included battery and charger, like the WORKPRO or DEWALT DCGG571M1, skips that separate purchase. Batteries never cross between brands, so platform choice locks in early.
Cartridge loading versus bulk filling for field work A 14 to 14.5 oz cartridge drops in clean and fast, ideal for a service truck making short stops all day. Bulk filling from a pail costs less per ounce over time but needs a loading pump and a few extra minutes per refill. Field techs covering many machines usually favor cartridges for speed, while a shop greasing the same equipment daily leans toward bulk fill savings. Compact guns under 14 inches, like the Performance Tool W50065, matter most for engine bays and undercarriage work where a full size gun will not fit.
How they compare
| # | Model | Max pressure | Best for | Score | Price |
|---|---|---|---|---|---|
| 1 | Milwaukee M18 2646-20 Cordless Grease Gun | 10,000 PSI | Best overall | 9.4 | Check price |
| 2 | Lincoln Lubrication 1264 PowerLuber 20V Cordless Grease Gun | 6,500 PSI | Best for heavy fleet use | 9.2 | Check price |
| 3 | DEWALT DCGG571M1 20V MAX Cordless Grease Gun Kit | 10,000 PSI | Best for DeWalt 20V MAX owners | 9.0 | Check price |
| 4 | Ryobi P620 18V ONE+ Cordless Grease Gun | 7,500 PSI | Best for Ryobi ONE+ owners | 8.7 | Check price |
| 5 | WORKPRO 20V Cordless Grease Gun Kit | 4,500 PSI | Best value | 8.4 | Check price |
| 6 | Craftsman CMCE521B V20 Cordless Grease Gun | 6,000 PSI | Best budget | 8.2 | Check price |
| 7 | Performance Tool W50065 12V Cordless Grease Gun | 4,500 PSI | Best for tight spaces | 8.0 | Check price |
Frequently asked questions
How much PSI does a cordless grease gun need?
Routine truck and mower fittings take grease under 3,000 PSI without issue. Old or packed fittings on farm and trailer equipment can need 6,000 PSI or more, so a gun rated near 10,000 PSI leaves margin for the worst cases.
How long does a cordless grease gun battery last on one charge?
Runtime tracks cartridge count more than time, since the pump only draws power while the trigger is pulled. A 4.0Ah pack on a gun like the DEWALT DCGG571M1 typically empties several full cartridges before needing a recharge, based on owner reports.
Can a cordless grease gun be filled from a bulk grease tub?
Most cordless models, including the Lincoln 1264 PowerLuber and Milwaukee M18 2646-20, accept a bulk fill accessory or manual loading through the barrel. It costs less per ounce than cartridges but takes a filler pump and a couple of extra minutes.
Is a cordless grease gun better than a pneumatic one?
Pneumatic guns usually hit higher sustained pressure and never need a battery, but they require an air compressor and hose running to the job. Cordless guns trade a little peak pressure for the ability to grease equipment anywhere on a lot or in a field.
Is a cordless grease gun worth it over a manual lever gun?
For anyone greasing more than a few fittings at a time, yes. A manual gun demands repeated pumping per fitting, while a cordless trigger clears the same point in seconds, based on owner comparisons between the two.
How do you clear a clogged grease fitting before greasing it?
Wipe the zerk fitting with a rag first, since dirt forced inside can block the ball check valve. A fitting that still won’t take grease after a few trigger pulls usually needs replacing rather than more pressure.
Can one brand’s battery power another brand’s grease gun?
No. Milwaukee M18, DeWalt 20V MAX and Ryobi 18V ONE+ packs only fit tools built for that specific platform, grease guns included.
How often should equipment fittings get greased?
Frequency depends on use and manufacturer guidance, but most trailer and farm equipment fittings need grease every 25 to 100 hours of operation, or roughly monthly for lightly used gear.
The verdict
Pick the Milwaukee M18 2646-20 as the strongest overall buy, since its 10,000 PSI rating and M18 battery compatibility cover both stubborn fittings and an existing tool fleet. Techs greasing heavy equipment all day should choose the Lincoln Lubrication 1264 PowerLuber instead, for its purpose built pump. Anyone just keeping a truck and mower serviced can skip both and save with the Craftsman CMCE521B V20.
