The LCN 4040XPT is a heavy-duty track arm door closer used on commercial doors across schools, hospitals, office buildings, and institutional facilities. When a part wears out or a component needs replacing, identifying the correct part number is critical. The track arm system on the XPT is different from the fixed shoe arm system on the standard 4040XP, and most parts do not cross over between the two models.

This guide covers every LCN 4040XPT part category: the cylinder assembly, covers, tracks, track arms, rollers, bumper assemblies, plugs, screw packs, and mounting plates. Each part number listed here links to the live product page at Security Parts, where you can confirm stock and order directly.

Quick Answer

LCN 4040XPT parts fall into six main categories: the cylinder assembly (part 3071), the cover (72 or 72MC), the track (3038 and variants), the track arm (3077T), the track roller (3034 or 3034H), and installation hardware including screw packs and mounting plates. The roller is sold separately from the arm and must be ordered as its own part.

• The 4040XPT uses a rolling track system, not the fixed shoe arm of the 4040XP. Parts are not interchangeable between the two models.
• Standard track is 3038. For hold-open, order 3038H. For a door stop built into the track, order 3038B or 3038HB.
• The 3077T track arm is non-handed and works on left- and right-hand doors. The 3034 track roller must be ordered separately.
• The cylinder assembly (3071) is the complete internal hydraulic unit. It is the most common major part replacement.
• Choose your screw pack based on substrate: SRT for metal, WMS for wood, TORX for torx screws, and TB prefix for thru-bolt mounting.
• For top jamb mounting, use the 18TJ drop plate. For narrow top rail or flush ceiling mounting, use the 18 drop plate.

How is the 4040XPT different from the 4040XP?

The 4040XPT and the 4040XP look similar from a distance, but the arm systems are completely different. This distinction matters because parts from one model do not fit the other.

The 4040XP uses a fixed shoe arm. The arm attaches directly to the door surface, and the shoe slides into a bracket mounted to the frame. There is no rolling track.

The 4040XPT uses a rolling track arm system. A track is mounted on the door frame header, and a roller travels along that track as the door swings open and closed. The track arm connects the closer spindle to the roller. This system provides a smoother, more controlled close cycle across the full range of motion.

The quickest way to confirm which model you have is to look at the door frame above the closer. If you see a metal track running horizontally across the frame with a roller that moves along it when the door opens, you have the 4040XPT. If there is no track and the arm connects directly via a shoe bracket, you have the 4040XP.

What is the 4040XPT cylinder assembly and when should it be replaced?

The 4040XPT-3071 Standard Cylinder Assembly is the hydraulic heart of the closer. It contains the piston, spring, and hydraulic fluid that control the door's closing speed and latching action. The 3071 is non-handed and fits both left-hand and right-hand doors.

Replace the cylinder assembly when the closer is leaking hydraulic fluid, when the door slams regardless of valve adjustments, or when the spring tension is weak and the door no longer closes fully. Minor speed adjustments are done through the valves on the existing assembly rather than replacing the whole unit.

• Part number: 4040XPT-3071
• Handing: Non-handed
• Application: Track arm closers only
• Stock: In Stock at Security Parts

Which cover does the LCN 4040XPT use?

The 4040XPT has two cover options: a standard plastic cover and a metal cover upgrade. Both protect the internal mechanism from dust and impact.

4040XPT-72 Standard Plastic Cover

The 4040XPT-72 is the standard plastic cover that ships with most units from the factory. It is non-handed, meaning the same part works on both left-hand and right-hand doors. Order this part for any standard cover replacement.

4040XPT-72MC Metal Cover

The 4040XPT-72MC is a metal cover for applications where added durability is needed. It is handed, so you must specify left-hand or right-hand when ordering. Choose this option for high-traffic doors, locations where vandalism or accidental impact is a concern, or installations requiring a higher-grade finish match.

Cover hardware

If the cover is in good shape but the hardware needs replacing, the following small parts are available separately:

• 4040XPT-31 Cover Screw - the screw that secures the cover to the body
• 4040XPT-54 Snap-On Cover Clip Only - the retention clip for snap-on covers

Which track do I need for the LCN 4040XPT?

The track is the metal rail mounted on the door frame header. It guides the roller and controls the door's swing path. There are four track variants for the 4040XPT, each suited to different functional requirements.

For most standard commercial door applications, the 3038 is the correct choice. The hold-open variants (3038H and 3038HB) are used when the closer needs to hold the door in an open position, such as in warehouses, loading docks, or spaces where doors are propped open frequently and need a built-in hold-open mechanism. The bumper variants (3038B and 3038HB) limit door travel and protect adjacent walls or fixtures.

How to identify which track is currently installed

Look at the track mounted on the door frame. A standard track is a straight rail with no visible stop mechanism at the far end. A bumper track has a physical stop built into the rail near the end of travel. A hold-open track has a detent or notch feature that catches and holds the roller when the door is pushed past a certain angle. If your door holds open at a fixed position when pushed fully open, you have a hold-open track installed.

Track arm and track roller: what is the difference between 3077T, 3034, and 3034H?

The track arm and the track roller are two separate parts that work together but are ordered individually. This is one of the most common ordering questions for the 4040XPT.

4040XPT-3077T Standard Track Arm

The 4040XPT-3077T Standard Track Arm is the arm that connects the closer spindle to the roller. It is non-handed and works on both left-hand and right-hand doors. The roller is not included with the arm and must be purchased separately as the 3034 or 3034H.

4040XPT-3034 Track Roller

The 4040XPT-3034 Track Roller is the wheel that travels along the track. It attaches to the end of the track arm. Order this part whenever the roller is worn, cracked, or not rolling smoothly. If you are replacing the arm, always replace the roller at the same time because a worn roller on a new arm increases wear on the new arm head.

4040XPT-3034H Hold-Open Track Roller

The 4040XPT-3034H Hold-Open Track Roller is a roller with a built-in hold-open function. It is used in combination with a hold-open track (3038H or 3038HB). If your door needs to hold open at a set position, this roller is needed along with the matching hold-open track.

4040XPT-425 Roller Lock Screw

The 4040XPT-425 Roller Lock Screw is the fastener that secures the roller to the track arm. If the roller comes loose during operation, this is the part to check and replace first before assuming the arm or roller itself is damaged.

What are the 78DE, 82, and 83H arm components?

Several sub-components make up the full track arm assembly. These are ordered when individual parts of the arm assembly fail rather than replacing the entire arm.

• 4040XPT-78DE Main Arm and Tube - the primary structural arm section that connects to the closer spindle. Order this when the main arm body is bent or broken.
• 4040XPT-82 Rod - the connecting rod within the arm assembly.
• 4040XPT-83H H Arm Screw - the fastener for the arm assembly.
• 4040XPT-73 End Cap - the cap at the end of the track or arm that provides a finished appearance and protects the open end.
• 4040XPT-3054 Hold Open Clip - a clip-on component used to add basic hold-open function. Order this when the hold-open function is needed but a full track swap is not practical.
• 4040XPT-159 Arm Screw - the screw that attaches the arm to the closer spindle.

What is the 4040XPT-169 bumper assembly and when is it used?

The 4040XPT-169 Bumper Assembly is an optional add-on that limits the door from opening past a certain angle. When installed, it reduces the maximum opening from 180 degrees to 110 degrees. This is useful when there is a wall, fixture, or obstruction behind the door that could be damaged if the door swings fully open.

The 169 is an alternative to ordering a bumper track (3038B or 3038HB). If you already have a standard 3038 track installed and want to add a stop without replacing the track, the 169 bumper assembly can be added to the existing setup. If you are installing a new track and know you need a stop, ordering the 3038B or 3038HB from the start is more efficient.

What are the 4040XPT-141-1 and 141-2 plugs?

The 4040XPT-141-1 and 4040XPT-141-2 are valve plugs. They seal the hydraulic adjustment ports on the closer body when those ports are not in use. If a port plug is missing or damaged, hydraulic fluid can leak from the adjustment port, causing the closer to lose speed control or leak entirely. These small parts are worth keeping on hand as replacements during any major service.

Which LCN 4040XPT screw pack do I need?

The correct screw pack depends on two things: the substrate you are mounting into and the mounting method. The 4040XPT uses finish-matched screws, so the pack you order must match the closer finish as well.

The TB prefix always means thru-bolt. Thru-bolt mounting passes the screw through the door frame or door from one side to the other, secured by a nut on the back side. This method is used when the substrate is not thick enough to hold a screw in place by thread engagement alone, or when the application requires extra pull-out resistance. If you are not sure which type was originally installed, check whether the mounting screws visible on the face of the closer go all the way through the door or frame to a backing nut. If they do, use a TB screw pack.

LCN 4040XPT mounting plates: 18 vs 18TJ

Mounting plates are used when the closer cannot be mounted directly to the door face or the soffit of the frame due to physical clearance limitations.

• 4040XPT-18 Drop Plate - used for narrow top rail or flush ceiling mounting. This drop plate positions the closer body lower than the standard location to provide clearance when the door frame header has a narrow top rail or when there is a flush ceiling above the door that would interfere with standard mounting.
• 4040XPT-18TJ Drop Plate (Top Jamb) - used for top jamb mounting. When the closer is mounted on the vertical face of the top jamb rather than the door face or frame soffit, this plate provides the proper offset and mounting surface. Top jamb mounting is common on out-swing doors where the door face is exposed to the exterior and a standard bracket mount is not suitable.

How do the valve adjustments work on the LCN 4040XPT?

The 4040XPT uses the same closer body as other 4040 series closers, so the valve system operates the same way. There are three main adjustment valves: the sweep speed valve, the latch speed valve, and the backcheck valve.

• Sweep speed controls how quickly the door moves through the main arc of its travel from fully open down to approximately 10 to 15 degrees from closed.
• Latch speed controls the final closing motion from approximately 10 to 15 degrees to fully closed. Adjusting this separately allows the door to snap into the latch without slamming.
• Backcheck creates resistance when the door is opened quickly or with force. It cushions the door before it reaches the mechanical stop or bumper to protect the closer arm and door hardware from impact damage.

All three valves are accessible on the closer body. Turn the valve screw clockwise to increase resistance (slower close or stronger backcheck) and counterclockwise to reduce resistance (faster close or lighter backcheck). Small adjustments of one-quarter turn are enough in most situations. If the door continues to slam after valve adjustment, the sweep speed valve may be fully closed or the cylinder assembly may need replacement.

For the complete parts listing with live stock and pricing, visit the LCN 4040XPT model page at Security Parts. You can also browse all LCN door hardware parts or explore the full commercial door closer parts catalog. For more LCN door closer guidance, see the LCN 4040XP parts guide and the LCN door closer parts guide.