Technical Service Bulletin
Date: February 3, 2025
Bulletin Name: FDM-TSB-004
Model: Oshkosh S-Series 2.0
Units Affected: SN 829379 - 829766

2.0 Load-Span Tag Axle (LSTA)
Piston Accumulator Pressure Check
Purpose:

This bulletin provides information and instructions for visually inspecting the LSTA piston accumulators to make
sure the correct pressure accumulators were installed on the vehicle. A group of incorrect pressure accumulators
were sent by the supplier and may have been installed on vehicles built between 8/1/2024 to 10/2/2024. A visual
inspection of the accumulator label will determine if the correct accumulators were installed.

Notice:
• This bulletin should be read and understood in its entirety before performing this procedure.
• All procedures outlined in the bulletin must be performed by skilled service personnel. Refer to the product
service manual for descriptions of maintenance procedures.

SAFETY NOTICE

SAFETY NOTICE

Perform your company’s Lockout/Tagout
procedure. If your company does not have a
Lockout/Tagout procedure, follow OSHA
1910.147 and 1910.146 Confined Space as
appropriate.

Use appropriate Personal Protective
Equipment (PPE) as required by your
company.

Procedure:

Lockout/Tagout

1. Place unit on a flat surface, block truck tires, and perform your company’s Lockout/Tagout procedure. If your
company does not have a Lockout/Tagout procedure, follow OSHA 1910.147 and 1910.146 Confined Space as
appropriate.
2. The vehicle’s BATTERY DISCONNECT switch is located on the left-hand side of the battery box. Use the
battery disconnect switch when performing any maintenance so the vehicle cannot accidentally be started.
a. Turn the battery disconnect switch (Figure A, Item 1) counterclockwise so the hole on the switch aligns
with the hole in the bracket (Figure A, Item 2).
b. Install the safety lockout device ring (Figure B, Item 1) through the holes on the battery disconnect switch
and the bracket.
c. Install a padlock (Figure B, Item 2) onto the safety lockout device ring, lock it, and put the key in your
pocket. If more than one person is working on the vehicle, each person must install his or her own padlock.

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Figure A

Figure B

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Piston Accumulator Inspection

3. Locate the two piston accumulators mounted inside the left-hand frame rail at the rear of the vehicle. See
Figure 1.

Piston
Accumulators

Figure 1

4. Inspect the piston accumulator labels and make sure one piston accumulator is pre-charged to 1200 PSI and
the second is pre-charged to 300 PSI. See Figure 2.
If the vehicle has an incorrect PSI piston accumulator installed contact Parker’s mobile hydraulic account
manager. Parker will set up an appointment to have a Parker technician come to your location and correct the
piston accumulator pressure at no cost to you.
Grant Noll – Mobile Hydraulic Account Manager
(440) 226-2537
[email protected]

Correct
1200 PSI

Correct
300 PSI

Figure 2

2

Incorrect
500 PSI

5. Remove lockout/tagout and wheel chocks.

Reimbursement of Costs

Affected units shall be inspected using the customer’s own qualified service technicians - at no cost to the owner.
The inspection should take approximately 30 minutes to complete.

Labor Reimbursement

In order to receive inspection credit, claims are to be submitted through the normal warranty claim system. Claims
must be received within 30 days of the repair. Claims must include the serial number of the truck, the customer
asset number, and the number of this bulletin.

Parts Reimbursement

Parker will adjust the accumulator for no cost. Contact Parker’s mobile hydraulic account manager to set up an
appointment for a Parker technician to come to your location and correct the piston accumulator pressure.
Grant Noll – Mobile Hydraulic Account Manager
(440) 226-2537
[email protected]

Deadline

If required, this service update should be performed at the earliest opportunity. For labor reimbursement, a
warranty claim form with proof of pressure adjsutment from Parker must be submitted by August 3, 2025.

Contacts

If you have questions or need further information, please contact a McNeilus National Service Representative at
888-686-7278.

Continuous Improvement:

The change included in this document is part of the
McNeilus Continuous Improvement Process.
McNeilus’s quality policy is providing customer satisfaction
through innovative products, dedicated service, and a
constant focus on continuous improvement.
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(888) 686-7278
www.streetsmartparts.com