Pressure Switch Threads May Become Stripped – 2020 Oshkosh S-Series

August 24, 2020 NHTSA CAMPAIGN NUMBER: 20V499000

Pressure Switch Threads May Become Stripped

As a result of a pressure switch air leak, the braking distance may be diminished and/or the parking brake may automatically engage. If the vehicle is equipped with an affected brake switch on both the front and the rear brakes and both parts fail, the brake lights may not operate. These conditions may increase the risk of a crash.

 

NHTSA Campaign Number: 20V499

Manufacturer Oshkosh Corporation

Components SERVICE BRAKES, AIR, PARKING BRAKE, EXTERIOR LIGHTING

Potential Number of Units Affected 312

 

Summary

Oshkosh Corporation (Oshkosh) is recalling certain 2020 S-Series vehicles equipped with Bendix pressure switches. The plastic threads holding the two halves of the pressure switch may strip when the switch is pressurized, resulting in an air leak which, if severe enough, can cause the air system to lose pressure when the brakes are applied. Failure of the front and rear brake switches will also result in a loss of brake light functionality.

 

Remedy

Oshkosh will notify owners, and dealers will inspect the brake pressure switch and replace it as necessary, free of charge. The recall began September 28, 2020. Owners may contact Oshkosh customer service at 1-888-686-7278.

 

Notes

Owners may also contact the National Highway Traffic Safety Administration Vehicle Safety Hotline at 1-888-327-4236 (TTY 1-800-424-9153), or go to www.safercar.gov.

 

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SAFETY NOTICE

VSR-TSB-028

NHTSA Campaign Number: 20V-499

Vehicle Safety Recall – Technical Service Bulletin

PROMPT ACTION REQUIRED

 

Attention:	Oshkosh Product Owner
Subject:	Bendix Pressure Switch
Models Affected:	Oshkosh S-Series Front Discharge Mixer
Model Year:	2020
Date:	September 2020

 

Purpose:

A concern affecting safety exists in some Oshkosh S-Series Front Discharge Mixers. Trucks have been identified that are equipped with Bendix pressure switches with damaged plastic housing threads. If the switch(es) fail an air leak will develop ranging from a small leak to a larger leak causing a loss of pressure in the vehicle air system. Loss of pressure in the vehicle air system will result in diminished braking of the vehicle or automatic engagement of the parking brakes. Failure of both switches will result in a loss of brake light functionality. This bulletin describes how to inspect and replace affected pressure switches.

Important: Do not run or use the vehicle if the pressure switches are faulty. Contact S-Series Service Support at 888-686-7278 immediately.

 

Affected Vehicles:

The affected vehicle population is Oshkosh S-Series Front Discharge Mixers produced in 2020. Please refer to the attached VIN list of affected vehicles.

 

Time Completion:

Complete the enclosed procedure for each affected truck. The time of accomplishment may vary due to a number of factors; however, the estimated time for inspection is 30 minutes, and the estimated time for replacement is 30 minutes under normal circumstances.

 

Required Action:

Review and verify your ownership of all affected serial numbers of Oshkosh vehicles. Oshkosh records indicate that you are the owner of one or more affected trucks, a Serial Number List is enclosed. Please be reminded that it is a violation of Federal law for you to sell or lease the vehicles covered by this notification until this recall has been performed on these vehicles. Substantial civil penalties apply to violations of this law.

 

Reimbursement of Costs:

Affected trucks shall be inspected using the customer’s own qualified service technicians – at no cost to the owner. The inspection should take approximately 30 minutes. The replacement of affect switch(es) should take approximately 30 minutes.

 

Parts/Labor Reimbursement:

In order to receive 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 Oshkosh VIN of the vehicle, the customer asset number, and the number of this bulletin.

 

Contacts:

If you have questions or need further information, please contact S-Series Service Support at 888-686-7278

 

Enclosures:

Procedure

VIN List of Affected Vehicles

 

Parts Required:

Item	Part Number	Description	Qty.
1	4133101	SWITCH, PRESS, SPST, BKLT	2

 

WARNING

For trucks without a battery disconnect switch, to prevent accidental vehicle start-up, which could cause death or serious injury, disconnect battery cables (negative cable first) before proceeding.

Disconnect negative (-) battery cable first. If positive (+) cable should contact ground with negative (-) cable connected, the resulting sparks can cause a battery explosion, which could result in death or serious injury.

 

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.

 

SAFETY NOTICE

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

 

PROCEDURE: Bendix Pressure Switch Inspection and Replacement

Preparation and Inspection

Important: Do not run or use the vehicle if a Bendix pressure switch is defective. Contact S-Series Service Support at 888-686-7278 immediately.

1. Park vehicle on flat, level surface. 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. Chock wheels.

2. Battery Disconnect Switch

 

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.

3. Locate the two Bendix pressure switches installed on the brake treadle valve, see Figure 1.

4. Check the pressure switch lot number date code label. Suspect lots include 12/19 and 01/20. See Figure 1.

 

Inspection Results and Actions

A. If either of the pressure switches lot number date code label does not include 12/19 or 01/20 this procedure is complete and no further action is required. Remove 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. Remove the wheel chocks. Return the vehicle to service.

B. If either of the pressure switches lot number date code label includes 12/19 or 01/20 or the date code label is missing Do not run or use the vehicle, maintain your company’s Lockout/Tagout on the vehicle, and replace the pressure switch(es) per the replacement procedure.

 

Replacement

1. Disconnect harness connections from the pressure switch.

2. Loosen and remove the pressure switch from the brake treadle valve.

3. Apply Loctite^® 567 sealant to the threads of new pressure switch.

4. Install pressure switch in brake treadle valve. Final tighten pressure switch hand tight plus 2-3 turns.

5. Reconnect harness connections to pressure switch.

 

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.

(888) 686-7278
www.streetsmartparts.com

 

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1 Affected Product

Vehicle

MAKE	MODEL	YEAR
OSHKOSH	S-SERIES	2020

 

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12 Associated Documents

Recall 573 Report- Amendment 4

RCLRPT-20V499-5908.PDF 213.851KB

 

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Recall Quarterly Report #2, 2020-4

RCLQRT-20V499-9592.PDF 211.224KB

 

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Recall 573 Report- Amendment 3

RCLRPT-20V499-3918.PDF 213.828KB

 

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Remedy Instructions and TSB

RCRIT-20V499-9383.pdf 1247.482KB

 

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Remedy Instructions and TSB

RCRIT-20V499-9418.pdf 1312.645KB

 

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Recall 573 Report- Amendment 2

RCLRPT-20V499-4532.PDF 213.831KB

 

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Recall Acknowledgement

RCAK-20V499-2210.pdf 245.017KB

 

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Recall Quarterly Report #1, 2020-3

RCLQRT-20V499-5820.PDF 211.122KB

 

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Recall Quarterly Report #3, 2021-1

RCLQRT-20V499-5034.PDF 211.309KB

 

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Recall 573 Report- Amendment 1

RCLRPT-20V499-7470.PDF 213.833KB

 

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Recall Quarterly Report #4, 2021-2

RCLQRT-20V499-5823.PDF 211.416KB

 

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Recall Quarterly Report #5, 2021-3

RCLQRT-20V499-3461.PDF 211.52KB

 

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Latest Recalls Documents

https://www-odi.nhtsa.dot.gov/acms/cs/documentList.xhtml?docId=20V499&docType=RCL

 

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Last update on 2026-05-23 / Affiliate links / Images from Amazon Product Advertising API

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