Oshkosh trucks are rugged, reliable, and built to handle the toughest conditions in military, fire, and severe-duty commercial applications. Maintaining proper engine oil levels is essential for performance, longevity, and safety.
In this guide, we present a detailed Oshkosh Truck Engine Oil Capacity Chart, covering various models across categories such as military, airport rescue, fire apparatus, and heavy-duty chassis trucks.
Oshkosh Truck Engine Oil Capacity Chart
| Model | Engine Type | Year Range | Oil Capacity (Quarts) | Oil Viscosity (SAE) |
|---|---|---|---|---|
| Oshkosh M1070 HET | Caterpillar C18 | 1990–Present | 42 | 15W-40 |
| Oshkosh M1070A1 HET | Detroit Diesel Series 60 | 2000s–Present | 38 | 15W-40 |
| Oshkosh M1075 PLS | Caterpillar C15 | 2000s–Present | 40 | 15W-40 |
| Oshkosh M977 HEMTT | Detroit Diesel 8V92TA | 1982–2000 | 36 | 15W-40 |
| Oshkosh M983 HEMTT | Detroit Diesel 8V92TA | 1980s–2000 | 36 | 15W-40 |
| Oshkosh HEMTT A4 (All Variants) | Caterpillar C15 ACERT | 2008–Present | 40 | 15W-40 |
| Oshkosh M1120 LHS | Caterpillar C15 | 2000s–Present | 40 | 15W-40 |
| Oshkosh MK23 MTVR | Caterpillar C12 | 2000s–Present | 36 | 15W-40 |
| Oshkosh MK48 LVS | Detroit Diesel 8V92TA | 1980s–1990s | 36 | 15W-40 |
| Oshkosh M911 LVS | Detroit Diesel 8V92TA | 1980s–1990s | 36 | 15W-40 |
| Oshkosh P-19 ARFF | Detroit Diesel 8V92TA | 1980s–2000s | 36 | 15W-40 |
| Oshkosh P-23 ARFF | Detroit Diesel 8V92TA | 1980s–1990s | 36 | 15W-40 |
| Oshkosh P-24 ARFF | Detroit Diesel 8V92TA | 1990s–2000s | 36 | 15W-40 |
| Oshkosh P-25 ARFF | Detroit Diesel 8V92TA | 1990s–2000s | 36 | 15W-40 |
| Oshkosh Striker 1500 | Scania DC16 V8 | 2010s–Present | 42 | 5W-40 (Synthetic) |
| Oshkosh Striker 3000 | Scania DC16 V8 | 2010s–Present | 42 | 5W-40 (Synthetic) |
| Oshkosh Striker 4500 | Scania DC16 V8 | 2010s–Present | 42 | 5W-40 (Synthetic) |
| Oshkosh S-Series Front Discharge | Cummins L9 | 2010s–Present | 30 | 15W-40 |
| Oshkosh S-Series (Legacy) | Cummins ISM | 1990s–2000s | 36 | 15W-40 |
| Oshkosh H-Series Snow Plow | Cummins ISX | 2000s–2010s | 42 | 15W-40 |
| Oshkosh H-Series (Legacy) | Cummins N14 | 1980s–1990s | 38 | 15W-40 |
| Oshkosh M984 HEMTT Wrecker | Detroit Diesel 8V92TA | 1980s–2000s | 36 | 15W-40 |
| Oshkosh LVSR (Logistics Vehicle System Replacement) | Caterpillar C15 ACERT | 2009–Present | 40 | 15W-40 |
| Oshkosh M-ATV | Caterpillar C7 | 2009–Present | 28 | 15W-40 |
| Oshkosh FMTV A2 | Cummins 6.7L Turbo | 2020s–Present | 26 | 15W-40 |
| Oshkosh Medium Tactical Vehicle (MTVR) | Caterpillar C12 | 2000s–Present | 36 | 15W-40 |
| Oshkosh J-Series (Desert Prince) | Cummins ISX15 | 2010s–Present | 44 | 15W-40 |
| Oshkosh J-Series (Desert Knight) | Cummins ISX15 | 2010s–Present | 44 | 15W-40 |
| Oshkosh R-Series | Caterpillar C13 | 2000s–Present | 38 | 15W-40 |
| Oshkosh E-Series (Cab-over) | Caterpillar C15 | 2000s–Present | 40 | 15W-40 |
| Oshkosh W-Series (W-700) | Cummins ISM | 1980s–1990s | 36 | 15W-40 |
| Oshkosh W-Series (W-1600) | Cummins ISX | 1990s–2000s | 42 | 15W-40 |
| Oshkosh W-Series (W-2200) | Cummins ISX | 1990s–2000s | 42 | 15W-40 |
| Oshkosh Global HET | Caterpillar C18 | 2010s–Present | 42 | 15W-40 |
| Oshkosh JLTV (Joint Light Tactical Vehicle) | Duramax 6.6L V8 Turbo | 2019–Present | 25 | 15W-40 |
Note: Oil capacities and viscosities may vary based on specific engine configurations. Always consult the vehicle’s owner’s manual for precise specifications.
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Notes on Maintenance and Oil Change Intervals
- Military Vehicles: Change engine oil every 6,000 miles or annually, whichever comes first, depending on deployment and usage.
- Fire & Rescue Units: Due to idle times and emergency readiness, oil should be changed at least every 12 months, even if mileage is low.
- Commercial Oshkosh Trucks: Follow OEM intervals (typically 15,000–25,000 miles) but adjust based on usage intensity and environmental conditions.
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Best Practices for Oshkosh Truck Oil Maintenance
- Check Oil Level Weekly: Especially in heavy-use environments.
- Use OEM-Approved Oils: Always use oils that meet or exceed OEM specifications like API CK-4 or CJ-4.
- Warm Up Before Draining: Warm oil flows more easily and removes more sludge.
- Replace the Oil Filter: Always change the oil filter when replacing oil.
- Keep Records: Maintain logs of oil changes for fleet management and warranty claims.
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FAQs
What type of oil does an Oshkosh HEMTT use?
Most HEMTT models use 15W-40 diesel engine oil, meeting API CI-4 or higher specs.
How much oil does an Oshkosh M1070 take?
The M1070 HET takes 42 quarts of engine oil.
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Can I use synthetic oil in Oshkosh trucks?
Yes, synthetic oils (like 5W-40) are often recommended for extreme cold or high-performance models such as airport rescue vehicles.
Where is the oil fill port on an Oshkosh truck?
Oil fill ports are typically located on top of the engine valve cover. Refer to the operator’s manual or engine layout.
How do I know if I overfilled the oil?
Check the dipstick after the engine has been idle for 5–10 minutes. If oil exceeds the full mark, drain the excess.
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Final Thoughts
Oshkosh trucks are built to last through harsh conditions, but their engines rely on proper lubrication to perform at their best. This engine oil capacity chart provides essential information to keep your vehicle in top condition. Whether you’re managing a military HEMTT or a commercial front-discharge truck, using the correct amount and type of oil can dramatically extend engine life and reduce downtime.
