Pacbrake GMC 2500 Alpha HD Air Suspension Kit Instruction Manual
- June 16, 2024
- Pacbrake
Table of Contents
Pacbrake GMC 2500 Alpha HD Air Suspension Kit
Product Information
Specifications:
- Product Name: Air Spring Kit
- Compatibility: Chevy/GMC 2500/3500 (2WD/4WD)* (will not fit vehicles equipped with Curt 5th wheel packages)
- Application: Leveling truck’s stance, eliminating sag, sway, and bottoming out, providing added support for a smooth & safe ride
- Manufacturer: L6575
- Model: L6575_REV2_07.17.2023 ECN 1-2779
- Chemical Warning: This product contains Hexavalent Chromate, which is known to the State of California to cause cancer and birth defects or other reproductive harm.
Product Usage Instructions
Important Notes:
- Read the entire manual before starting the installation.
- This air suspension kit will not increase the GVWR (Gross Vehicle Weight Rating) determined by the vehicle manufacturer. Do not exceed the maximum capacity listed by the vehicle manufacturer.
- The air bag must have clearance to prevent contact with surrounding components when inflated or compressed. Trim any excess bolt length to avoid contact with the bag or other suspension components.
Safety Warnings:
- Improper installation, air spring pressure operation, or maintenance can result in serious personal injury or death. Follow instructions, safety recommendations, and maintenance suggestions.
- Inflating an unsecured air spring is dangerous and can cause serious personal injury or death. Always secure the air spring to the vehicle before inflating it.
- Removing and replacing air springs should only be done by a qualified service professional with proper training, tools, and equipment.
Kit Contents:
Refer to the kit explosion diagram for part assembly.
HD (5000 lbs) Kit Contents:
- 2 x HP10000
- 4 x HP10054
- 2 x HP1100
XD (7500 lbs) Kit Contents:
- 2 x HP10438
- 4 x HP10069
- 2 x HP1245
Required Tools:
This kit requires the following tools:
- Test/fill air springs tool (not specified)
Before Starting the Installation:
- Ensure the application information matches the make, model, and year of the vehicle.
- Check with the manufacturer if the vehicle is equipped with a rear wheel brake proportioning valve, as it may affect braking performance.
- Use a good quality anti-seize on all fasteners to prevent corrosion and ease future removal if necessary.
- Note: This kit contains push-to-connect fittings. Cut the nylon airline squarely with the nylon hose cutter provided in the kit or a sharp utility knife to avoid distortion and connection leaks.
FAQ
Q: Can I use this air suspension kit on a vehicle equipped with a Curt 5th wheel package?
A: No, this air suspension kit is not compatible with vehicles equipped with Curt 5th wheel packages.
Q: Can exceeding the maximum capacity listed by the vehicle manufacturer increase the GVWR?
A: No, the GVWR (Gross Vehicle Weight Rating) is determined by the vehicle manufacturer and cannot be increased by using this air suspension kit. Do not exceed the maximum capacity specified by the manufacturer.
Q: Is it safe to inflate an unsecured air spring?
A: No, inflating an unsecured air spring is dangerous and can result in serious personal injury or death. Always secure the air spring to the vehicle before inflating it.
WARNING: This product can expose you to the chemical Hexavalent Chromate, which is known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov
Thank you and congratulations on the purchase of an air suspension kit. Please read the entire manual prior to starting the installation to ensure you can complete it once started.
IMPORTANT
This air suspension kit will not increase the GVWR (Gross Vehicle Weight Rating), as the GVWR is determined by the vehicle manufacturer. Do not exceed the maximum capacity listed by the vehicle manufacturer.
PLEASE NOTE: The air bag must have clearance between itself and the surrounding components to prevent any contact when bag is infl ated or compressed. Trimming off excess bolt length is also required to ensure no contact with the bag or other suspension components can be made once installed.
Safety Warnings!
- Serious personal injury or death may result from an air spring failure or accident due to improper installation or air spring pressure operation or maintenance. Please read and abide the instructions, safety recommendations and maintenance suggestions throughout this manual.
- Inflating an unsecured air spring is dangerous. If it bursts, it could be hurled into the air with explosive force resulting in serious personal injury or death. Never infl ate an air spring unless it is secured to the vehicle.
- Removing and replacing air springs can be dangerous. This is only a job for a qualifi ed service professional. Never perform air spring service procedures without proper training, tools, and equipment.
KIT CONTENTS
Reference the kit explosion diagram on the following page for part assembly.
HD (5000 lbs) KIT CONTENTS QTY PART #
A *| Double Convoluted Air Bag, 2500 lb each| 2| HP10000
B **| Roll Plate, 4.5” Diameter| 4| HP10054
C ***| 90° Swivel Fitting, ¼” Hose to ¼” NPT| 2| HP1100
HD (5000 lbs) KIT CONTENTS QTY PART #
A *| Double Convoluted Air Bag, 2500 lb each| 2| HP10000
B **| Roll Plate, 4.5” Diameter| 4| HP10054
C ***| 90° Swivel Fitting, ¼” Hose to ¼” NPT| 2| HP1100
XD (7500 lbs) KIT CONTENTS QTY PART #
A *| Double Convoluted Air Bag, 3750 lb each| 2| HP10438
B **| Roll Plate, 5.5” Diameter| 4| HP10069
C ***| 90° Swivel Fitting, 3/8” Hose to 3/8” NPT| 2| HP1245
KIT CONTENTS QTY PART #
D| Bracket, Upper Driver| 1| HP1884
E| Bracket, Upper Passenger| 1| HP1885
F| Bracket, Lower| 2| HP1886
G| Axle Strap| 2| HP0128
H| Round Strap| 2| HP0016
I| U-Bolt, 4.25” x 6.5” Square| 2| HP1331
J| Bolt, 3/8”-16 x ¾” Countersunk| 8| HP1008
K| Bolt, 3/8”-16 x 2.5” Carriage| 4| HP1005
L| Bolt, 3/8”-16 x 3.5” Carriage| 4| HP1332
M| Bolt, M8x1.25 x 25 mm Flange| 2| HP1430
N| Nut, 3/8”-16 Nylon Lock Flange| 12| HP1975
O| Heat Shield| 1| HP0012
P| Worm Gear Ring Clamp| 2| HP1001
REQUIRED TOOLS
-
Hoist or Floor Jack
-
Safety Stands
-
Safety Glasses
-
Torque Wrench
Standard Combination Wrenches -
7/32” Hex Allen Wrench
-
1-1/8” Wrench or Deep Socket
-
Ratchet
-
Metric & Standard Sockets
-
Hose Cutter (included) or Sharp Utility Knife Pipe Thread Sealant
-
Spray Bottle with Dish Soap/Water
-
Air Compressor/Compressed Air Source (to test/fill air springs)
-
Pry bar or large screwdriver (optional)
BEFORE STARTING THE INSTALLATION:
- Ensure the application information is correct for the make, model and year of the vehicle you are installing the kit on.
- Some vehicles are equipped with a rear wheel brake proportioning valve. Check with the manufacturer before installing the air spring kit, as it may affect braking performance.
- It is recommended to use a good quality anti-seize on all fasteners. This will reduce the chance of corrosion on the fasteners and will help facilitate removal, if required at a later date.
PLEASE NOTE:
This kit contains push-to-connect fittings; using scissors or wire cutters to cut the nylon airline will distort the line and cause the connection to leak. THE AIRLINE MUST BE CUT OFF SQUARELY WITH THE NYLON HOSE CUTTER PROVIDED IN THIS KIT OR A SHARP UTILITY KNIFE.
Please make sure all the items shown in this explosion diagram are provided in your kit before starting the installation.
ASSEMBLY SHOWN
HD (5000 lb) KIT PASSENGER SIDE ASSEMBLY SHOWN:
PLEASE NOTE:
- A* HD – HP10000 / XD – HP10438
- B** HD – HP10054 / XD – HP10069
- C*** HD – HP1100 / XD – HP1245
Installation Instruction
LIFT VEHICLE
- Place wheel chocks in front of and behind both front wheels.
- Raise the rear of the truck high enough to attain a comfortable working height.
- Place two jack stands under the axle.
- Lower the vehicle until the frame is supported by the jack stands (as shown in Figure 1).
REMOVE JOUNCE BUMPER
Remove the jounce bumper from the retaining cup on the frame (as shown in Figure 2).
- A pry bar or large screwdriver may be needed to pry out the jounce bumper.
UNBOLT BRAKE LINE BRACKETS
- Remove the bolt securing the brake line bracket to the strike plate on the axle on both sides of the vehicle (see Figure 3 for reference). Gently pull the bracket with brake lines away from the strike plate.
ASSEMBLE AIR SPRINGS
Assemble air springs as shown in Figure 4A (HD kit driver side shown as reference). Set the roll plate and lower bracket over the bottom of the air spring. Align the holes in the lower bracket (as per Figure 4B) which details the correct bolt holes to use for each side of the vehicle. Secure using two 3/8”-24 countersunk bolts. Torque bolts to 27 N•m [20 ft-lbs] Install the swivel air fitting into the largest hole in the top of the air bag, hand tight plus 1.5 turns.
Some air fittings have sealant pre-applied on threads. If no visible coating is present, apply a thread sealant or Teflon tape before assembling to help prevent leaks. Set the roll plate and respective driver or passenger side upper bracket on the air spring. Secure using two 3/8”-24 countersunk bolts. Torque bolts to 27 N•m [20 ft-lbs]
INSTALL SPRING ASSEMBLIES
PLEASE NOTE: It may be necessary to raise the frame of the truck a few inches to allow more clearance to install the air spring assemblies. Position the air spring assembly such that the lower bracket rests on the jounce bumper strike plate and the upper bracket nests around the jounce bumper retainer. (See Figure 5 for reference) The air fitting will be positioned on the inboard side of the frame.
ATTACH BRAKE LINE BRACKET
Attach the brake line bracket (previously removed in Step 3) to the lower bracket of the air spring kit using the original mounting hole and the longer M8 bolt provided in this kit.
- Torque bolt to 25 N•m [19 ft-lbs]
INSTALL AXLE STRAP
Insert a 3/8”-16 x 2.5” carriage bolt through each slot in the lower bracket. Place the axle strap on the axle and secure using the carriage bolts and two 3/8”-16 flanged nylon lock nuts.
- Torque flange nuts to 27 N•m [20 ft-lbs]
SECURE UPPER BRACKET
Install the square U-bolt around the frame of the vehicle and through the mounting holes in the upper bracket (as shown in Figure 8A). Ensure no brake lines or wires are pinched between the U-bolt and the frame. Install a 3/8”-16 flanged nylon locking nut on each end of the U bolt. Do not fully tighten yet.
Insert two 3/8”-16 x 3.5” carriage bolts into the large slots on the upper bracket. Place the round strap around the jounce bumper retainer and onto the carriage bolts (as shown in Figure 8B). Secure the strap using two 3/8”-16 flanged nylon locking nuts. Torque flange nuts on round strap to 20 N•m [15 ft-lbs] Torque flange nuts on square U-bolt (installed in the previous step) to 20 N•m [15 ft-lbs]
INSTALL HEAT SHIELD
Bend tabs on the heat shield so the required ½” of dead space exists between the heat shield and exhaust when attached. Attach the heat shield to the exhaust pipe on passenger side using two ring clamps (shown in Figure 9). Each hose clamp holds a tab against exhaust pipe.
INSTALL AIR LINE
PLEASE NOTE: This kit contains push-to-connect fittings; using scissors or wire cutters to cut the nylon airline will distort the line and cause the connection to leak. THE AIRLINE MUST BE CUT OFF SQUARELY WITH THE NYLON HOSE CUTTER PROVIDED IN THIS KIT OR A SHARP UTILITY KNIFE Provided in air spring kit are two fill valves. The most common place to install is in place of license plate fasteners. Alternatively, two 5/16” holes can be drilled in a convenient location. Cut air line assembly into two equal lengths with hose cutter. Install one air line, route the nylon air line to an air spring fitting and cut the hose. Moisten the end of the air line prior to inserting it into the fitting and push it in until it stops. Repeat with the other fill valve. Secure airlines using the tie-straps, away from moving items and heat sources. Place a 5 ⁄16” nut on the air valve. Leave enough of the inflation valve in front of the nut to extend through the hole, install a flat washer, and 5 ⁄16” nut and cap (reference Figure 10 for assembly). There should be enough valve exposed after installation—approximately ½”—to easily apply a pressure gauge or an air chuck.
If an in-cab inflation kit is being installed, follow the instructions provided with that kit now.
CHECK SYSTEM FOR LEAKS
Inflate both air springs to 90 psi and then use a mixture of dish soap and water on all air line connections to detect any air leaks. Large, expanding bubbles indicate a leak (as shown in Figure 11). Repair as necessary and retest. Inflate air springs to a predetermined value and on following day recheck pressure. If one or both of air springs have lost pressure, an air leak is present. Leak must be repaired, and then retested until no leaks exist.
AFTER COMPLETING THE INSTALLATION
PLEASE REMEMBER:
Install wheels and torque fasteners to manufacturer’s specifications. Re- torque all fasteners after first 500 miles of driving. For safe and proper operation, never operate the vehicle under minimum of 10 psi or over maximum of 100 psi in air springs. Staying within pressure limit will ensure maximum air spring life. Failure in doing so may result in a void warranty. Do not exceed maximum vehicle payload. Failure to do so my result in failure of the air suspension kit and/or damage to your vehicle.
Thank you again, and congratulations on the installation of the air suspension kit.
OPTIONAL ACCESSORIES
Optional dual needle air gauges are available to monitor pressure in each spring from vehicle cab, as well as a full line of air compressors, air tanks, and solenoids built to work with and control your air spring system.
OPERATING YOUR VEHICLE WITH AIR SUSPENSION
Air springs have minimum and maximum pressure requirements. Never operate your vehicle with less than 10 psi in air spring and never infl ate air springs over 100 psi. Damage to air springs will result. Check air pressure in air springs daily for fi rst couple of days to ensure a leak has not developed. Air springs are designed to maintain the vehicles stock ride height with a load. Do not use the air springs as a means to lift vehicle with no load. This will result in a harsh ride.
SERVICING YOUR VEHICLE WITH AIR SUSPENSION
When lifting the vehicle with a floor jack or hoist on the frame, never allow the air spring to limit the travel of the axle. Try to always jack the vehicle on the axle. Suspending the axle with the air spring limiting the axle travel will damage the air spring and void the air spring warranty.
WARRANTY
The owner’s warranty will be void if air springs are run with less than the minimum of 10 psi. See additional warranty for details.