Page 1 of 3
®
3-T’s RV Products, Inc.
-------
INSTALLATION INSTRUCTIONS FOR THE T-9WH HEAVY DUTY SYSTEM AIR FOR THE WORKHORSE CHASSIS 15,000 TO 18,000 GVW
PARTS LIST: 2 Air sleeve assemblies consisting of air sleeves
attached to the top and bottom mounting brackets
4 5/16" x 3 1/2" bolts
4 5/16" Top lock nuts
4 1/2" x 1-1/2" bolts
47/16 Flat Washer Grade 8
41/2" Flange nuts
28’ Airline assembly with Air valve.
1Information pack
READ ALL INSTRUCTIONS THOROUGHLY BEFORE BEGINNING THIS INSTALLATION.
Lift the vehicle at the differential. Place jack stands under the frame. Lower the vehicle onto the stands. Remove the rear wheels. Divide the parts in this kit into two separate groups, one for each side. Place the air sleeve assembly over the spring with the hook portion of the adjustable slider around the forward U-bolt. See Figure 1.
Take a tape measure and measure between the rubber down stop and top of the axle. NOTE: ON SOME VEHICLES THERE IS AN UP STOP ON THE AXLE. Whatever the measured distance is, the distance between the top and bottom bracket must be twice the measurement when drilled. If the measurement is 4" there must be 8" between the top and bottom bracket of the air bags. After this is done, align the top with the bottom bracket with weight of the vehicle on the springs. Using a 1/2" drill, drill through the top bracket to mark the frame for the center of the holes. NOTE: CHECK INSIDE OF FRAME FOR BRAKE & FUEL LINES BEFORE DRILLING. Start drilling using a 1/8" drill, then a 3/8" drill. Finish the hole with the 1/2" drill.
Place the 1/2 x 1-1/2" bolts through the washers then through the front and rear holes of the top bracket. Use 1/2" lock nuts and torque to 75 foot-pounds.
1055 EMPIRE DRIVE LAKE HAVASU CITY, AZ 86404
(928) 453-3040 USA: (800) 223-1779 FAX (928) 453-3140
Install the 5/16" x 3 1/2" bolts through the two holes closest to the bottom of the springs. Place nuts on these bolts, but do not tighten. Double check the alignment of the air sleeves. The allowABLE tolerance is +/- 1/8". PROPER ALIGNMENT MEANS THAT THE RUBBER ON THE AIR SLEEVES IS STRAIGHT UP AND DOWN, PERPENDICULAR TO THE TOP AND BOTTOM BRACKETS WITH LOAD OF UNIT ON SPRING. After this is done, tighten the two adjustment nuts on the bottom bracket to 20 foot pounds and the top bracket air sleeve bolts to 40 INCH POUNDS.
Repeat all the above steps on the opposite side of the vehicle.
Route the airlines out to the wheel well opening area, securing away form all sharp edges, exhaust pipes, ect. Drill a 5/16" hole so that the air valve can be mounted through the body structure. Remove the cap, nut and one washer from the fitting. Slide the fitting through the hole in the sidewall. Replace washer, nut and cap and tighten nut. Refer to Figure 2 for exact placement of these parts. Install the air pressure decal next to the air valve.
Inflate the System Air to 30 psi to seat the lower bracket against the spring. With a full load on the axel, check the alignment of the air sleeves. With 30 psi in the sleeves, you should NOT be able to feel the piston located about one inch above the bottom of the air sleeve. If you feel the piston, the air sleeve is not aligned properly. Re-adjust the bottom bracket to proper alignment if needed. When you are sure the assembly is straight, tighten the nuts on the 3-1/2" bolts. Tighten to full length of threads (strap will bend under spring).
Inflate the air sleeves to 100 psi. Check all fittings for air leaks with a soapy water solution. Release the air pressure until the vehicle sits level.
Units can carry from 20 to 100 PSI under load, fill to accommodate the load and keep the vehicle level. Individual owners may require different pressures to suit their own concept of best ride. Units must contain a minimum of 20 psi at all times. Do not drive the vehicle without air in the System Air.
Recommended installation time for the System Air: 1.5 hours
US Patent 4,494,772 et al.
Note: Brackets may be different depending on coach.
Doc.#: II1850
Creation Date: 1/7/05Rev.#:Rev Date: