2025 Ram Chassis Cab Maintenance Schedule
Complete Service Intervals for 3500, 4500 and 5500 Chassis Cab HEMI V8 and Cummins Turbo Diesel Commercial Powertrains
Proudly serving Brevard, Asheville, Hendersonville, Fletcher & Cherokee NC
2025 Ram Chassis Cab Scheduled Maintenance Overview
The 2025 Ram Chassis Cab (3500, 4500 and 5500) is the commercial workhorse of the lineup, built to be upfit with service bodies, dumps, flatbeds, tow rigs and more, and 2025 is the first year of the redesigned truck with a TorqueFlite HD 8-speed automatic and electronic column shifter behind both engines. The 6.4L HEMI V8 (375 hp / 429 lb-ft in chassis-cab tune) is standard on all three series and the 6.7L Cummins Turbo Diesel (360 hp / 800 lb-ft) is available on all three; both are PTO-capable. One schedule covers every series because the engines are identical across 3500, 4500 and 5500, but gas and diesel follow different plans, and Class 3, 4 and 5 duty cycles demand strict adherence to them. Stellantis BusinessLink fleet programs help offset cost and minimize downtime.
The 2025 Ram Chassis Cab uses the Stellantis Oil Change Indicator System on both engines. The HEMI plan says to never exceed 8,000 miles, 12 months or 350 engine hours between oil changes. The Cummins plan allows up to 15,000 miles, 12 months or 500 engine hours, with 7,500-mile / 6-month columns for tire rotation, DEF refills and front-end lubrication. Long hours of PTO operation, stop-and-go route work and loaded mountain grades bring the indicator on sooner, which is exactly what the engine-hour caps are for, so fleets should plan on the indicator, not the maximum.
Oil & Filter
HEMI: Oil Change Indicator; max 8,000 mi / 12 months / 350 hours
Cummins: max 15,000 mi / 12 months / 500 hours
Tire Rotation
HEMI: every 10,000 mi / 1 year (sooner at irregular wear)
Cummins: every 7,500 mi / 6 months
Cabin Air Filter
Every 12,000 mi (both engines)
Mopar 68548579AA
Spark Plugs
HEMI: 100,000 mi (16 plugs, mileage based)
Cummins: none; two fuel filters every 15,000 mi
Complete Maintenance Schedule by Mileage
| Mileage Interval | Services Performed |
|---|---|
| Every 7,500 miles / 6 months | Check DEF tank and refill; rotate tires; lubricate front end; inspect CV/universal joints |
| Every 8,000 miles (Oil Change Indicator; max 8,000 mi / 12 months / 350 engine hours) | Change engine oil and filter; inspect exhaust; rotate tires at first sign of irregular wear; inspect batteries; inspect CV/universal joints; inspect brakes and parking brake; inspect cooling system; lubricate front end; inspect engine air cleaner (dusty/off-road) |
| Every 10,000 miles / 1 year (table columns) | Rotate tires; inspect CV/universal joints |
| Every 12,000 miles | Replace cabin air filter |
| Every 12,000 miles | Replace cabin air filter |
| Every 15,000 miles / 12 months | Replace engine-mounted fuel filter AND chassis-mounted fuel filter; inspect engine air cleaner (replace as needed; max 30,000 mi / 24 months); inspect front suspension, tie rod ends, boot seals |
| Every 15,000 miles (max 15,000 mi / 12 months / 500 engine hours) | Change engine oil and filter; inspect exhaust; rotate tires; inspect batteries; inspect CV/universal joints; inspect brakes; inspect cooling system; lubricate front end; inspect engine air cleaner |
| Every 20,000 miles / 2 years | Inspect front suspension/tie rod ends; inspect front/rear axle surfaces (change axle fluid for police, taxi, fleet, off-road, frequent towing); inspect brake linings and parking brake function |
| Every 22,500 miles / 18 months | Inspect brake linings; inspect/adjust parking brake; inspect drive belt; inspect front/rear axle surfaces (change axle fluid for severe use) |
| 30,000 / 60,000 / 90,000 / 120,000 miles (AS69RC) or 120,000 miles (8-speed) | AS69RC: change ATF every 30,000 mi and ATF + sump filter at 60,000/120,000; ZF 8-speed: change automatic transmission fluid and filter(s) at 120,000 mi |
| 30,000 / 90,000 / 150,000 miles (AS66RC transmission only) | Change automatic transmission fluid (AS66RC transmission only) |
| Every 30,000 miles / 24 months | Inspect wheel bearings; inspect transfer case fluid (4x4), change for police, taxi, fleet, frequent towing |
| Every 30,000 miles / 3 years | Replace engine air cleaner filter |
| 60,000 and 120,000 miles | Change transfer case fluid (4x4) |
| 67,500 and 150,000 miles | Replace crankcase ventilation (CCV) filter |
| 97,500 miles / 78 months | Flush and replace power steering fluid |
| 100,000 miles | Replace spark plugs (mileage based only); inspect and replace PCV valve if necessary |
| 120,000 miles | Change transfer case fluid |
| 10 years or 150,000 miles | Flush and replace engine coolant |
| 150,000 miles / 120 months | Flush and replace engine coolant (dealer-recommended service) |
Time-Based Service
Several 2025 Ram Chassis Cab items are governed by time as well as miles, whichever comes first:
- Engine oil and filter: at least every 12 months on either engine, even at low mileage (HEMI also caps at 350 engine hours, Cummins at 500)
- Tire rotation and CV/U-joint inspection: HEMI every 10,000 miles or 1 year; Cummins every 7,500 miles or 6 months
- Front suspension, axle and brake inspections: HEMI every 20,000 miles or 2 years; Cummins fuel filters and front suspension every 15,000 miles or 12 months, brake linings, drive belt and axles every 22,500 miles or 18 months
- Engine air filter: HEMI every 30,000 miles or 3 years; Cummins inspected every 15,000 miles and replaced by 30,000 miles or 24 months at the latest
- Cummins wheel bearing and transfer case inspection: every 30,000 miles or 24 months
- Cummins power steering fluid: flush and replace at 97,500 miles or 78 months
- Engine coolant: Mopar OAT coolant on both engines; HEMI at 10 years or 150,000 miles, Cummins at 150,000 miles or 120 months
- Brake fluid: the 2025 manual sets no replacement interval; DOT 3 brake fluid is inspected at every service
Engine-Specific Maintenance Details
The Ram Chassis Cab is offered in 3500, 4500 and 5500 series, and the engines are the same in all three: the 6.4L HEMI V8 is standard and the 6.7L Cummins Turbo Diesel is optional on every series. Note the chassis-cab ratings: the HEMI makes 375 hp / 429 lb-ft here (405 hp in the 2500/3500 pickups) and the Cummins is the 360 hp / 800 lb-ft version; the 430-hp High Output diesel is pickup-only. The HEMI uses SAE 0W-40 full synthetic (MS-A0921), 7.0 quarts with the Mopar 4892339BE filter, and 16 Mopar SP138239AC spark plugs replaced at 100,000 miles. The Cummins uses SAE 10W-30 above 0 F or SAE 5W-40 synthetic below 0 F meeting MS-10902 and API CK-4 (Cummins CES 20081 oils also acceptable), 12.0 quarts with the Mopar 68677810AA (Fleetguard LF16453) filter, and a Mopar 68645327AA engine air filter. Transmission fluid depends on the gearbox: the ZF 8HP75 (gas 3500 under 10,000-lb GVWR) takes Mopar ZF 8 & 9 Speed ATF, while the PTO-capable 8AP430 (gas 3500 over 10,000-lb GVWR, 4500 and 5500) and the diesel 8AP850 take Mopar ATF 818. Both engines share the Mopar 68548579AA cabin filter and Mopar OAT MS.90032 coolant.
| Specification | 6.4L HEMI V8 | 6.7L Cummins Turbo Diesel I6 |
|---|---|---|
| Oil Type | SAE 0W-40 full synthetic (MS-A0921) | SAE 10W-30 (above 0 F) or SAE 5W-40 synthetic (below 0 F) meeting MS-10902 and API CK-4 |
| Oil Capacity | 7.0 qt (with filter) | 12.0 qt (with filter) |
| Oil Filter | Mopar 4892339BE (per 2025 Ram 2500/3500 catalog - same 6.4L) | Mopar 68677810AA (Fleetguard LF16453) - Geno's lists fitment 2025-2027 3500/4500/5500 |
| Engine Air Filter | — | Mopar 68645327AA |
| Cabin Air Filter | Mopar 68548579AA (per Ram HD catalog - verify) | Mopar 68548579AA (verify) |
| Spark Plugs | Mopar SP138239AC (x16) (per Ram HD catalog - verify) | None (diesel) |
| Spark Plug Interval | 100,000 mi | — |
| Transmission Fluid | 8HP75: Mopar ZF 8 & 9 Speed ATF (or equivalent); 8AP430 TorqueFlite: Mopar Automatic Transmission Fluid (ATF) 818 (or equivalent) | Mopar Automatic Transmission Fluid (ATF) 818 (or equivalent) |
| Coolant | Mopar Antifreeze/Coolant 10 Year/150,000 Mile Formula OAT (MS.90032); 18.5 qt | Mopar Antifreeze/Coolant 10 Year/150,000 Mile Formula OAT (MS.90032); 22 qt (3500/4500 per manual) |
Commercial Fleet, Upfit & Class 3-5 Maintenance
Chassis Cab trucks are commercial vehicles, typically upfit with service bodies, dump beds, flatbeds, wreckers or vocational equipment, and the diesel adds items a gas truck never sees. The two Cummins fuel filters (engine-mounted 5-micron and chassis-mounted 3-micron, Mopar 68677800AA set) are replaced every 15,000 miles. The 8.7-gallon DEF tank is checked and refilled every 7,500 miles. The crankcase ventilation (CCV) filter (Mopar 68677813AA) is replaced at 67,500 and 150,000 miles and the power steering fluid is flushed at 97,500 miles. On the diesel's ZF 8AP850 8-speed, the 2025 manual calls for a fluid and filter change at 120,000 miles. The 2025 manual also retains legacy Aisin AS66RC and AS69RC transmission rows (30,000-mile fluid changes) that apply only to those gearboxes; the 2025 chassis-cab spec sheet lists only ZF 8-speeds and no fluid change is listed for the gas ZF, so confirm your transmission with our advisors. Transfer case fluid on a diesel 4x4 is changed at 60,000 and 120,000 miles; the HEMI 4x4 changes it at 120,000, or at 60,000 and 120,000 for police, taxi, fleet or frequent-towing use. Axle fluid is changed at the 20,000-mile (HEMI) or 22,500-mile (Cummins) inspection under those same severe conditions. Upfit bodies and PTO equipment carry the upfitter's own service schedule on top of the chassis plan.
- Upfit hardware (service bodies, dumps, PTOs, hydraulics) requires periodic inspection at every service.
- Power take-off (PTO) systems on upfit hydraulics have their own maintenance schedule — ask your upfitter.
- Commercial duty: 5,000-7,500 mi oil intervals; 2-year brake fluid; 30,000-60,000 mi transmission fluid.
- Stellantis BusinessLink fleet programs offer priority service scheduling and discounted preventive maintenance.
- DEF and fuel filter service is a recurring fleet operating cost — budget accordingly.
- Class 3-5 brake systems wear faster than light-duty — inspect every oil change.
- Upfit electrical loads benefit from auxiliary battery and alternator inspection.
- DOT-required CDL inspections augment but do not replace the manufacturer’s maintenance schedule.
Severe & Special Operating Conditions
Stellantis defines severe operating conditions as any of the items below: dusty or off-road driving, frequent trailer towing, and police, taxi or fleet use, which covers most chassis-cab duty by definition. The 2025 manual adjusts specific items accordingly: the HEMI's engine air cleaner is inspected at every oil change in dusty or off-road use, front and rear axle fluid is changed at the 20,000-mile (HEMI) or 22,500-mile (Cummins) inspection for police, taxi, fleet, off-road or frequent-towing use, and transfer case fluid is changed under the same conditions at the 30,000-mile / 24-month inspection (Cummins) or at 60,000 and 120,000 miles (HEMI) instead of only being inspected.
- Commercial duty cycle (most Chassis Cab use)
- Heavy payload (varies by class; typical 8,000-15,000 lbs)
- Heavy towing (varies by class)
- Extended idling (jobsite, PTO operation)
- Operating in dusty or jobsite conditions
- Sustained mountain grade driving (Western NC commercial)
- Extreme cold weather (below 0°F) or extreme heat (above 100°F)
- Frequent short trips between job sites
Service for 2025 Ram Chassis Cab Owners Across Western NC
Ram Chassis Cab fleets across Western NC handle construction, agriculture, utility service, towing and delivery work: around Brevard and Pisgah Forest, in Asheville, and throughout Hendersonville and Waynesville. Upfit service bodies, dumps and contractor beds on the 3500, 4500 and 5500 see heavy daily use. Mountain grades stress brakes under a loaded body. Hours of PTO work put engine hours on the clock faster than miles. Cold winter starts are exactly why the Cummins switches to 5W-40 synthetic below 0 F. Our BusinessLink-affiliated Mopar-certified team understands commercial fleet needs.
Monthly & Semi-Annual Owner Checks
Between scheduled service visits, a few quick owner checks help catch problems before they become repairs. These take only a couple of minutes and apply to every 2025 Ram Chassis Cab.
- Tire pressure — check before every loaded run; check inner duals on DRW.
- Engine oil level — check at every fuel fill-up for commercial Cummins use.
- Coolant level — verify weekly.
- DEF level — check at every fill-up.
- Brake fluid level — check weekly under heavy commercial duty.
- Upfit body mounting bolts — inspect monthly; commercial vibration loosens hardware.
- Fuel water separator — drain at every fill-up.
- Hydraulic / PTO equipment — inspect per upfit manufacturer’s schedule.
Note on Pricing: Chassis Cab service pricing reflects commercial duty. The Cummins takes 12 quarts of CK-4 oil versus 7 quarts of 0W-40 for the HEMI, its two fuel filters are a recurring 15,000-mile item, and DEF refills add to operating cost. Fleet operators should explore BusinessLink preventive maintenance contracts which lower per-service cost, and upfit hardware service may be separate from the chassis manufacturer's schedule. Call (828) 492-2121 for fleet quotes.
Schedule Your 2025 Ram Chassis Cab Maintenance at Mahon CDJR
Mahon CDJR is a BusinessLink-affiliated Ram dealer with Mopar-certified diesel technicians for the full 2025 Chassis Cab lineup (3500, 4500 and 5500), with the correct Mopar oil, filters and fluids for the 6.4L HEMI and 6.7L Cummins. Our team understands commercial fleet needs and offers scheduling that minimizes downtime. Schedule online or call our service team at (828) 492-2121 for fleet programs.
Created September 29, 2026 by MM Dealer Advocates