Frequently Asked Questions
Q: How strong is the G Coupler (LockNLube™) lock-on?
Q: Will grease discharge from the gun with the coupler unattached?
As long as you don’t pump the handle, no grease will come out. gaye farnsworth answered on June 25, 2015 If you have the G Coupler connected to the Gurtech™ G Gun, the patented pressure release valve will almost totally eliminate grease discharge out of the grease couple nozzle tip. When using the pressure release valve on the G Gun, the grease under pressure will be returned to the grease bucket canister. A further saving on wasted grease when greasing. Yes, it will. Oscar B. answered on June 25, 2015 Yes it will grease if it is on cert or off Merle Ellis answered on June 25, 2015 It works very well in hard to reach areas. melvin walters answered on June 25, 2015 Yes it will discharge grease if not on a grease fitting… Just like a regular grease gun end…. The reason I use one is on grease fittings that sometimes don’t take grease at first, you can release the jaws break the seal and remove the grease gun end from the fitting were normally you have to pull, twist and yank to get it off the fitting while under pressure which generally damages the grease gun end jaws and/or seal and next time you use it leaking is very common… This is not going to happen with the LockNLube one since you can easily remove the grease gun end from… » Read More G & A Stone answered on June 25, 2015 Yes it will Virginia B. answered on July 25, 2015
Q: Will I have enough room around u-joints or through a PTO shield?
I have had no problem accessing you joints. The business end sticks out far enough so the lever does not interfere. I don’t have a shield on my application. Erland Lofquist answered on September 15, 2016 On some of the tight ones you may not. I just keep a hand grease gun for those fittings. Amazon Customer answered on September 15, 2016 Hello Mitch, Thank you for your question, and for your interest in our LockNLube Grease Coupler! The Coupler is only slightly larger than a standard coupler. But there will be some places that it cannot reach. Its dimensions are: Dimensions L: 3½ x W: ⅗ x H: 1⅗ In (L: 88 x W: 16.4 x H: 41 mm) Diameter (front coupler) ⅗ in (16 mm). Fits most recessed Zerks (grease nipples). I hope that information is helpful to you in determining if it will fit for your application. If you have any other questions, please don’t hesitate to call us at 603-795-2298. Lock and Lube LLC SELLER answered on September 15, 2016 UPDATE!!! We have released an extended tip version of the G Coupler for this exact application. The dimensions are as follows: L: 5½ x W: 31/32 x H: 1½ In (L: 88 x W: 16.4 x H: 41 mm)
Q: What is the outside diameter of this coupler?
The diameter is 5/8″ Danny W answered on August 3, 2015 The diameter of the barrel is 1mm bigger than the standard coupler. Lock and Lube LLC SELLER answered on August 3, 2015 5/8 inch scott silva answered on August 10, 2015
Q: Can this work with a regular grease gun without air? Any recommendations on a grease gun? I will using this on my CNC machine. Thnx!
Never used on manual gun works great on my air which is a Lincoln from northern tool Gary Henry answered on September 18, 2015 Hi there, The LocknLube coupler will work with any grease gun with a 1/8″ NPT thread. As far as grease guns go I like a lever gun because I feel that I have more control over the grease and because the coupler locks on both of my hands are free to work the gun. Lock and Lube LLC SELLER answered on September 18, 2015 We put ours on a Dewalt 18V grease gun and it works great. I don’t see why it would not work just as well on a manual gun. We use ours for our trackhoe, backhoe and large farm tractor and equipment. It saves a lot of time with the power gun. Steve S. Williams answered on September 18, 2015 I also have one on my regular grease gun and I absolutely can not say enough good things about it. Any farm supply store will have a grease gun for you. You just have to replace the old tip with the Lock ‘n Lube and you are ready to go. Amazon Customer answered on September 18, 2015 Any grease gun will work. Just be sure that the grease gun you are does not exceed 10000lb. pressure. Richard answered on September 18, 2015 Yes fits any standard grease gun end. Neil Guiles answered on September 18, 2015 It can be used on a regular grease gun. It is not good for small — tight areas. onion48 answered on September 18, 2015 Yes. I use a hand pump and have no trouble. Works like a champ. I am going to order 2 more Derrell B. answered on September 19, 2015
Q: Work in a lot tight spaces, do any of you users find it difficult to use it in tight areas?
Yes. It is large, but does a great job when it does fit. I have changed some fittings to make them more accessible Amazon Customer answered on May 25, 2016 I don’t want to be without one. I farm and do alot of greasing on tractors, planters and all kinds of equipment and found just a few tight places to grease Tom Eibling answered on May 25, 2016 Yes, doesn’t work well in tight spots diyer answered on May 25, 2016 I have it on a flexible hose. It is easier in tight spaces because I do not have to hold pressure on it while pumping. It is harder in some really small spaces because it is longer than a small fitting on a flexible hose, so it may not work because of this. In balance, it is much easier and I like it. MiWilder answered on May 25, 2016 Yes. It is longer than a standard zero coupler and so in tight spaces it may present a problem connecting to a fitting. I use it primarily on tractors and zero turn mowers where I generally have more room. Works great. John McNulty Jr answered on May 26, 2016 It does take a little more room, but it hasn’t been a problem. Samuel N Geesaman answered on May 26, 2016 yes; not good in very tight spots but workd great otherwise sassy answered on July 28, 2016
Q: Will this fit on a 90 degree grease fitting screwed onto Moog upper ball joint?
Yes I have greased my 2002 f-350 front end with it By eric sieczkowski on August 30, 2016 Yeah it should. I used mine to lube my Moog ball joint. By A Taylor on August 28, 2016 The LockNLube Grease Coupler should fit for the application you described. If it doesn’t, the coupler comes with a full money-back satisfaction guarantee, so you can return it at no cost! By Lock and Lube LLC SELLER on August 29, 2016
Q: Do needle adapter sleeves fit over the end?
It will fit some sleves and not others. It will work just fine without the sleeve. So if the sleeve is too small remove it. If the sleeve fits leave it in place. Either way it will work just fine By Lock and Lube LLC SELLER on April 25, 2016 I use several different grease needles for those hard to get at places and haven’t had any problems. I just push handle on Lock N Lube down and insert the grease zerk that has the needle attached and release handle By Tom Eibling on April 25, 2016 yes By John D. Sargent on April 25, 2016 No. It will fit all zero fittings. In my business there are metric and standard, fits them all no problem. This tool rocks!! By Michael Thomas on April 24, 2016 I haven’t tried, but I don’t know why they wouldn’t. By Samuel N Geesaman on April 24, 2016 No the coupler screws to the hose on your grease gun By Corn 760 on April 26, 2016
Q: How long is this fitting? Not sure it will fit where I need it to.
Thank you for your question, and for your interest in our LockNLube Grease Coupler! The dimensions of the Gurtech™ G. Coupler (LockNLube®) Grease Coupler are as follows: L: 3½ x W: ⅗ x H: 1⅗ In (L: 88 x W: 16.4 x H: 41 mm) Diameter (front coupler) ⅗ in (16 mm). Fits most recessed Zerks (grease nipples). I hope this is helpful. If we can provide any further info, please don’t hesitate to call +1-603-795-2298. By Lock and Lube LLC SELLER on September 28, 2016 It is about 3 inches long, however if you can get it attached it works very well. By DAVID TURK on September 28, 2016 3 1/2 inches. Total length By Roy Bush on September 27, 2016 it will get in about a tite of spot as reg. fitting with a hose—-DDT. By Amazon Customer on September 27, 2016 This coupler will work in most locations. It is about three inches long from tip to where the lever begins. It won’t work in real tight locations. The ease of use makes it well worth the price. By Charles V. Stark on September 28, 2016 The useable length of the fitting 1.67 inches. By John M. Bodak on September 27, 2016 3″ without hard fitting on hose By 67159zenda on September 28, 2016
Q: What exactly does the nitrile rubber seal?
UPDATE!! The G Coupler is fitted with a seal that is more durable that the industry standard Nitrile rubber seal Since mid 2016, all new Gurtech™ couplers are fitted with a new improved seal. The new seal is a custom rubber formulation, designed specifically for Gurtech™ and, is therefore unique to the Gurtech™ couplers. This new seal has an even better performance and durability than the industry standard nitrile rubber seal. The new specification rubber seal was designed to be more durable against damage by sharp burrs present on damaged zerk fittings.
It seals around the fitting so when you are locked on it won’t leak grease By Thomas allyn gage on October 2, 2014 It maintains the seal around the zerk so the pressure of the grease is not lost around the fitting By KP on October 13, 2014 It seals around the outside of the zerk so the grease goes into the end of the zerk By Michael Kercewich on October 4, 2014
Q: It is just the fitting or does it include the flexible line?
Its the fitting. There is no flexible line. By Cory on March 27, 2015 This is the fitting only, but it fits all standard lines, this is excellent quality and will save lots of aggravation especially in hard-to-reach places. Be sure to clean fitting with rag to extend the life of this coupler. I highly recommend. By tom delong on March 25, 2015
Q: Where is this product manufactured?
Also: Where is the G. Coupler manufactured? Where is the Gurtech™ Coupler manufactured? Where is the LockNLube Coupler manufactured? Where is the G. Gun foot operated grease gun manufactured? Where is the G. Gun bucket grease pump manufactured? Product of South Africa. By Rick Goggins on August 8, 2014 The product is 100% manufactured in KwaZulu-Natal, South Africa by the designers and patent holders; Gurtech™ (Pty) LTD.
Q: After installing it, I couldn’t depress the gun’s pump. What did I do wrong?
Your grease cert may be plugged, other than that I am sure you have grease in gun. Take coupler off and see if your gun will pump if it does get back to amazon you may have bad coupler By John A. Rieder on July 10, 2015 There might be a check valve causing the problem as in the hose direction could possibly be reversed. Try a new hose? My grease coupler pumps thru very easily. By FreshAir4Me on July 11, 2015 Between myself and friends we have successfully installed five of these fittings without any problems. As per the other reviews, I would first check your gun to see if was in fact pumping grease, then reinstall the coupler and try again, before you put it on a fitting. Could be that the fitting jerk that you tried it on was frozen. If it still does not allow grease to flow, it is defective and you will need to return it. By Green Rider on July 10, 2015 If no grease comes out of the gun when the coupler is on the hose but not on a fitting you may have a defective coupler. Contact the seller for replacement. By Lock and Lube LLC SELLER on July 10, 2015
Q: How is this product different from Gurtech™?
Didn’t know about Gurtech™ until your question. They appear to be identical. By Gumby on August 28, 2016 Hello Elias, Thank you for your question, and for your interest in our LockNLube products. The LockNLube Grease Coupler is manufactured by Gurtech™. The same item is available from other resellers, labeled as a ‘Gurtech™ G.Coupler’ instead of a LockNLube Grease Coupler. The LockNLube Grease Coupler comes with a full money-back guarantee, as well as a free replacement seal kit and free shipping. Thanks again for your interest! By Lock and Lube LLC SELLER on August 29, 2016 I don’t know nothin bout no Gurtech™. I can answer questions bout this thang though By David Reynolds on August 28, 2016
Q: Will this work on various sized fittings?
The LockNLube grease coupler was designed to work on a large range of sizes. Whether they are Metric or standard. By Lock and Lube LLC SELLER on December 28, 2015 It works on all the fittings that I have use it on, it is worth the money. By Thomas Vonderhaar on December 28, 2015 It works on all the fittings that I have use it on. By Amazon Customer on December 28, 2015 works on metric and standard, if your refering to fitting that have a angle turn such as a 90 degree or 45 degree it still works. Fitting on small ujoints that have small opening between yoks it will not work. By Gary Edler on December 27, 2015 If you are referring to zerk fittings, everyone I have ever encountered in the last 45 years has been the same size. By David L. Fuseler on December 27, 2015 Yes it will work on different size fittings By Kerry J. Simon on December 27, 2015
Q: Does this work with Milwaukee grease guns?
If it has a grease coupler on it now, that will work. They work very well By Michael Thomas on March 16, 2016 As far as I know, all grease gun parts are universal so this tip will just screw on. By chris saunders on March 17, 2016 should work on any brand By Lance on March 16, 2016 The answer to this question is somewhat complicated. The standard LockNLube coupler has a 1/8″ NPT hose connection. This will be compatible with all US grease guns EXCEPT SOME of the 18 volt Milwaukees. It appears that Milwaukee imported a batch of 18 volt guns that have 10×1 Metric thread on the coupler end of the hose – unlike the majority of Milwaukee 18 volt guns, which have the standard 1/8″ NPT thread. There is no way to tell what the thread is without taking off the coupler and then test fitting a known 1/8″ NPT onto the hose end to see if it works. If the known 1/8″ NPT does not thread on, it is likely that you have one of the Milwaukees with the 10×1 Metric thread. There are indications that the most recent Milwaukee 18 volts are now coming through with the standard 1/8″ NPT thread again, and not the 10×1 Metric. There are several solutions:
  1. Determine the thread type on your grease gun – chances are, there may be no problem at all with just using a standard 1/8″ NPT thread LockNLube coupler.
  2. Replace the original hose with a new Milwaukee hose Part # Milwaukee 49-16-2647. The new replacement hoses are 1/8″NPT. The thread size is printed right on the front of the package. Your LockNLube coupler will then connect properly to the replacement hose.
  3. Contact LockNLube, by calling 603-795-2298. They now have couplers with Metric threads and will be more than happy to help work through this problem with you.
Hope that helps! By Lock and Lube LLC SELLER on March 16, 2016
Q: What’s the width of the head or tip of the coupler, i.e. the size of the slide?
The diameter of the tip of the coupler is 16 mm (0.63 inches). The length of the slide body is 15 mm (0.59 inches). The length of the coupler body is 78 mm (3.07 inches). The length of the coupler from tip to release handle is 88 mm (3.46 inches).
Q: What is the highest pressure I can use with the G Coupler grease coupler?
Our internal testing has had the Lock and Lube™ coupler seal on the Zerk nipple at 690 bar (10,000 psi) consistently (see demonstration of grease coupler sealing under high pressure). This means you can use the Lock and Lube™ Coupler on heavy-duty industrial pumps and pneumatic grease pumps with pressure ratings up to 690 bar (10,000 psi). Ensure that all your fittings and pipes are well maintained and correctly specified for the pressure you will be using. A hose that bursts under high pressure can cause grease to penetrate your skin. This is a serious health risk. When combined with the G.Gun, you can easily build enough pressure to jack the tracks on your industrial crawler equipment – in the field.
Q: What grease guns does the G Coupler grease coupler fit onto?
Here’s a list of compatible grease guns that the G Coupler fits onto: – Lincoln – Lumax – Alemite – Plews lubrication (Edelmann) – Grainger – SKF – John Deere – Macnaught – Sealey – Draper … almost any grease gun should work The G Coupler grease coupler can be used on manual lever action, pistol grip, trigger action, battery powered (cordless) and pneumatic (air operated and powered) greasing equipment.
Q: Is there a follower plate on the G.Gun?
No. With the G.Gun you are always refilling into the same canister, so although you will never pump out all the grease, the small amount of “dead” grease is essentially only lost on the first filling thereafter it’s a closed self-lubricating system. Our experience is that, by it’s very nature, a follower plate is the major cause of contaminants being introduced into the grease. The biggest disadvantage with a follower-plate design, is that when a pump is being changed from one pail to another, the likelihood of contaminants attaching to the grease on the follower plate is very high. This is now a 12 inch (300 mm) diameter disc covered in grease which is a super stick magnet for anything – especially airborne dust. On the poorer quality units, the grease can also find its way to the top of the follower plate. So when refilling is required, there is a good chance that grease will fall on the floor.
Q: How well does the coupler handle 000.00 grease?
Yes, you can use the G Coupler with (NGLI) 000.00 grease. Disconnection may be slightly messy though.
Q: How much grease is dispensed per stroke?
The G.Gun grease gun dispenses a theoretical 3cc per stroke. Our tests confirm the actual volume dispensed is 2.7cc/stroke. The difference has to do with the time the valves take to close. Should a specific volume be required, a person can count the number of strokes they pump. When it comes to greasing precision bearings, it is possible that they can be over greased and cause more damage than good. In these cases, some form of accurate metering should be used. There are companies that sell metering units that be fitted in-line on the hose.
Q: How long is the greasing pipe? Do you offer longer pipes?
Our units are sold standard with a 6.5ft (2m) hose. Longer hose lengths can be purchased as a spare item, generally these go up to 16ft (5m). We have also supplied lengths up to 33ft (10m).
Q: How does the G.Gun compare with competing products?
The G.Gun is more portable and user friendly than the pail type guns. The larger capacity canister requires less frequent filling than the hand held and battery powered grease guns (like the Powerluber™). You spend less time refilling your grease gun and more time greasing those joints. It is a lot more ergonomic to use your foot to pump rather than bending down and pumping a pail on the ground. This allows for faster greasing. The hand held type with the pistol grip, are very fatiguing to pump. The G.Gun has a lot more leverage on the treadle, requiring less effort to pump. Pneumatic (air powered) and electric/battery powered systems that are used in more organised workshop environments, rather than on site, will always be faster than any manual system. But then, when one is in the field, you won’t have to worry about flat batteries, car chargers, replacing expensive batteries or having compressed air handy.
Q: Does the G.Gun get air-locks like my current grease gun?
It is extremely seldom that you will experience an air-lock on a G.Gun. Most pumps are single stage with a relatively small swept volume. This is the prime cause for air locks, where any air drawn in through the top of the grease down a ‘vortex’ can then create an airlock. The G.Gun’s internal mechanism creates a wave action preventing a vortex and the two stage pump copes with any air that may be trapped in the grease.
Q: Can I use the G.Gun in very dusty environments? I’m always struggling with contaminated grease being wasted.
The unit has a clip-on lid that prevents dust contaminating the grease. The complete pump unit is incorporated inside the grease canister so there are no external seals. Most other grease guns have the piston protruding outside the grease reservoir, which is then in turn attached to some lever mechanism via some form of linkage. Where the piston comes out, dust will be attracted to the residual grease on the piston rod and after use, eventually damaging the seal, causing bypass. This can end up being very messy. Also where the external linkages get dirt and dust in them, they will wear a lot quicker. All the G.Gun moving parts are incorporated within the grease canister and therefore submerged in and always lubricated by the grease.
Q: Can I use the G Coupler Grease Coupler to lubricate in very tight places or in recessed fittings?
As a high pressure, heavy duty grease coupler, it will fit into the majority of recesses (the diameter on the front is 0.63in (16mm), only 0.04in (1mm) greater than most standard push-on couplers). The diameter of the G Coupler coupler is smaller than a number of the most common heavy duty grease couplers. While the G Coupler coupler is compatible with most recesses and nipple placements, it may not fit into very tight or some recessed spaces. Accessibility to the odd hard-to-reach zerk, can often be resolved by fitting a different variation of Zerk grease fitting. One with a longer neck, shorter neck, 45 degree bend, right angle (90 degree) bend, etc. These fittings are usually low cost items that are very easy to replace. We have had a couple of questions about this, but in the end our customers still believe that this small shortcoming is greatly outweighed by the many benefits.
Q: Are any spare parts available?
Yes, the G Coupler (LockNLube® in North America) has a replaceable seal kit. The G Gun has the following spares available: Part No.Description GC81003Pump Unit (PRV) GC81004Lid OS61001Treadle Spring GC81006Valve Kit GC810072m Hose Assembly GC810083m Hose Assembly GC810094m Hose Assembly GC810105m Hose Assembly



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