Technical Service Bulletin 10001 THIS APPLIES TO ALL AIR SPRINGS USED IN USSC LLC AIR SUSPENSIONS Issue: USSC has made a change to the air spring used in operator seat suspensions. This bulletin will identify the air spring products and the type of suspensions that they employ. Products: Products affected are the 500lbs air suspensions p/n s 9901-612920-000, 9901-612920- 001, and the 375lbs air suspensions p/n s 9901-612913-000, 9901-612915-000, 9901-612916-000, and 9901-612940-000. Summary: There are two different air springs used on the 500lbs rated suspensions p/n s 9901-612920-000, and 9901-612920-001. There are two different air springs used on the 375lbs rated suspensions. The early edition air spring for the 375lbs suspension is no longer offered. Identification: 500lbs rated suspensions The 500lbs rated suspensions are identified by having the upper air spring mount located on the outer scissor or upper, and the lower air spring mount is located on the lower suspension frame. The early version 500lbs rated suspension is shown in Figure 1, and has used the 9903-500184-000 air spring shown in Figure 2. The USSC LLC discontinued date for this air spring used in the 500lbs rated suspension was 11/2009.
500lbs rated suspension, note lower spring mount location. Lower spring mount location at lower suspension frame Figure 1 (500lbs suspension shown) Outer scissor or upper scissor mount location Early version air spring p/n 9903-500184-000 Figure 2 (500lbs suspension shown) Lower suspension frame mount location The new 500lbs rated suspension air spring p/n 9903-500184-001 is shown in Figure 3, and shown installed into the 500lbs suspension in figure 4. This new air spring is the replacement for all 500lbs rated suspensions. The new air spring 9903-500184-001 is not compatible for use in the 375lbs lift rated suspensions shown later.
Air spring p/n 9903-500184- 001; also shown in 500lbs suspension shown below in figure 4. This is the 500lbs air spring replacement. Figure 3 Outer scissor or upper scissor mount location Lower suspension frame mount location Figure 4 (500lbs suspension shown)
Identification: 375lbs rated suspensions The 375lbs suspensions are identified by the orientation of the lower air spring mount shown in Figure 5 (375lbs suspension shown) and Figure 6. The top of the air spring mounting is located on the outer scissor or upper, while the lower air spring mounting differs from the 500lbs suspension. The lower air spring mount is located on the inner scissor or lower. 375lbs rated suspension, note lower air spring mount location. Lower spring mount location at inner or lower scissor Figure 5 (375lbs suspension shown) Air spring p/n 9903-500184-000; shown in the 375lbs suspension. This is the 375lbs air spring replacement. It can be identified by its composite top and bottom Figure 6 (375lbs suspension shown) The current air spring part number for the 375lbs suspension is p/n 9903-500184-000 see above Figure 6 (375lbs suspension shown).
This air spring p/n 9903-500184-000 is the replacement for the early 375lbs air spring shown below in Figure 7. The early air spring is no longer available. Metric air tubing and fitting were equipped with the early air spring Early air spring with cast aluminum top and bottom Figure 7 (Early 375lbs air spring) The early air spring in the 375lbs suspension can be identified by the cast aluminum top and bottom see Figure 7. This air spring contains a rigid metric 6mm air supply tube and inlet fitting that has metric threads. This air bag is no longer available as a replacement service part. The current version of the 9903-500184-000 air bag can be identified by the composite top and bottom see Figure 6 (375lbs suspension shown) and Figure 8.
Air spring p/n 9903-500184-000 fitted with 1/8 NPT elbow quick connect fitting and will adapt to ¼ outer diameter air tubing Air spring p/n 9903-500184-000 is the replacement for 375lbs air suspensions. Identified by composite top and bottom Figure 8 The current 9903-500184-000 air bag is fitted with 1/8 NPT threads in the top for the inlet fitting, and new mounting hardware. The metric fitting that worked in the original aluminum top and bottom air spring is not compatible for use in the air spring with composite ends. If suspension is equipped with the early air spring, modifications are required. Actions: USSC supplies a replacement air spring assembly for use in the 375lbs suspensions that has the original aluminum top and bottom air spring. The assembly 9901-500184-000 is supplied with a new push to connect tube fitting that has the correct 1/8 NPT threads for the air spring. Using this part number will require the use of ¼ outer diameter tubing, instead of the original 6mm tube. There are several ways to retrofit the suspension from 6mm tube to the required ¼ inch tube. Please contact USSC service for instructions and options to retrofit the original air spring configuration. USSC LLC supplies replacement air spring assemblies for use in varying suspensions, see Figure 9.
Contact: USSC LLC 150 Gordon Drive Exton, PA19341 USA Phone: 1-610-265-3610 Fax: 1-610-265-8327 Figure 9