The worst 2021 Oshkosh S-Series problems
Ranked by number of owner complaints. Mileage and cost come from what owners wrote.
Problems by type
Tap a problem to see which part fails, at what mileage and in which other years.
Recalls 7
Electrical system: alternator/generator/regulator
- What is wrong
- Oshkosh Corporation (Oshkosh) is recalling certain 2019-2022 S-Series 2.0 Concrete Mixers. Incorrectly installed alternator electrical cable clamps may rub against the vehicle frame or hydraulic hose, possibly damaging the alternator cables.
- Risk
- Damaged alternator electrical cables can increase the risk of a fire.
- Remedy
- Oshkosh will provide instructions on how to inspect the wiring, reposition the clamps, and properly secure the cables. The repair can be performed by the owner or an Oshkosh service center, free of charge. Owner notification letters were mailed on June 23, 2022. Owners may contact Oshkosh's customer service at 1‑888‑686‑7278.
Recall number 22V378000 · Recall details
Fuel system, diesel: fuel injection system: fuel rail
- What is wrong
- Oshkosh Corporation (Oshkosh) is recalling certain 2019-2022 S-Series vehicles. The fuel tubes between the fuel rail and the injector for cylinders 4, 5 and 6 may be susceptible to cracking, resulting in a high pressure fuel leak.
- Risk
- A high pressure fuel leak in the presence of an ignition source may increase the risk of a fire.
- Remedy
- On engines with 75 miles or less, dealers will install vibration isolators to the fuel tubes. Engines with more than 75 miles will receive new fuel tubes with vibration isolators. Repairs will be performed free of charge. Owner notification letters are expected to be mailed February 1, 2022. Owners may contact Oshkosh customer service at 1-8088-686-7278.
Recall number 22V008000 · Recall details
Suspension: multiple axle
- What is wrong
- Oshkosh Corporation (Oshkosh) is recalling certain 2019-2022 S-Series vehicles. The u-bolts securing the front axle may fail.
- Risk
- Bolt failure may allow the front axle to shift or detach, increasing the risk of a crash.
- Remedy
- Oshkosh will provide new u-bolts, free of charge. Owner notification letters were mailed February 24, 2022. Owners may contact Oshkosh customer service at 1‑888‑686‑7278.
Recall number 22V009000 · Recall details
Steering: hydraulic power assist: pump
- What is wrong
- Oshkosh Corporation (Oshkosh) is recalling certain 2020-2021 S-Series vehicles. A machining defect may cause pressure to build in the power steering pump and break the shaft seal, resulting in a loss of power steering assist.
- Risk
- A loss of power steering assist increases the risk of a crash.
- Remedy
- Owners will inspect and replace the power steering pump as necessary. Owners may perform this work themselves or reach out to one of our service centers to perform the inspection and repair work free of charge. Owner notification letters were mailed on December 15, 2021. Owners may contact Oshkosh customer service at 1‑888‑686‑7278.
Recall number 21V851000 · Recall details
Electrical system: wiring: fuses and circuit breakers
- What is wrong
- Oshkosh Corporation (Oshkosh) is recalling certain 2019-2022 S-Series vehicles. These vehicles were manufactured with 10 amp Anti-Lock Brake System (ABS) fuses, instead of the required 15 amp ABS fuses.
- Risk
- The incorrectly sized fuse may blow during an ABS braking event, increasing the risk of a crash.
- Remedy
- Oshkosh will provide owners new fuses, a new fuse label, and installation instructions, free of charge. Owner notification letters were mailed on July 29, 2021. Owners may contact Oshkosh customer service at 1‑888‑686‑7278.
Recall number 21V482000 · Recall details
Suspension: multiple axle
- What is wrong
- Oshkosh Corporation (Oshkosh) is recalling certain 2021 S-Series vehicles. The auxiliary axles may not have been properly secured and may detach.
- Risk
- A detached axle may cause a loss of vehicle control, increasing the risk of a crash.
- Remedy
- A technician will inspect and, as necessary, replace any improperly installed fasteners, free of charge. Owner notification letters were mailed on May 26, 2021. Owners may contact Oshkosh customer services at 1‑888‑686‑7278.
Recall number 21V322000 · Recall details
Power train: automatic transmission: internal: shaft: output
- What is wrong
- Oshkosh Corporation (Oshkosh) is recalling certain 2020-2021 S-Series vehicles. The rear axle output shaft may not have been heat-treated properly, which could cause the shaft to fracture.
- Risk
- A fractured rear output shaft may cause the shaft or interaxle driveline to detach from the vehicle, increasing the risk of a crash or injury.
- Remedy
- Oshkosh will notify owners, and owners will be instructed to inspect the output shaft, and if necessary, order a new one and replace it, free of charge. The recall began on March 31, 2021. Owners may contact Oshkosh customer service at 1‑888‑686‑7278.
Recall number 21V125000 · Recall details
Technical service bulletins for the 2021 Oshkosh S-Series 30
Bulletins tell dealers how to fix known problems. A warranty extension means the manufacturer pays for that repair for longer.
- This bulletin provides instructions for the inspection, weld repair, and installation of reinforcement...
- This bulletin provides instructions for identifying and locating all driveline grease zerk fittings
- This bulletin provides instructions to install the latest battery disconnect switch on S-Series 2.0...
- This bulletin provides instructions to install a check valve in the chute return hydraulic circuit to...
- This bulletin provides instruction for replacing the existing chute drive washer with a hardened steel washer
- This bulletin provides information on verifying powertrain harness grounds are correctly installed, and...
- This bulletin provides information on making sure the dedicated ground from the battery negative to the...
- This bulletin provides information on installing metal door linkage rod clips in place of original plastic...
- This bulletin provides instruction for replacing a Micronet display with an updated Grayhill overhead...
- This bulletin provides instruction for installing an updated water meter.
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Questions about the 2021 Oshkosh S-Series
Is the 2021 Oshkosh S-Series reliable?
Owners have filed 0 complaints about the 2021 Oshkosh S-Series.
What is the most common problem with the 2021 Oshkosh S-Series?
There are not enough complaints to tell.
How many recalls does the 2021 Oshkosh S-Series have?
7 recalls, covering electrical system, fuel system, diesel and suspension.
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