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2008 DODGE RAM 3500

6.7L I6 Cummins Diesel•4WD•AUTOMATIC•diesel
5-Year Cost of Ownership
$26,797 maintenance + known platform issues
~$5,359/yr · 450¢/mile equivalent · $15,725 maintenance + $9,552 expected platform issues
Compare this engine
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5.7L V8 Hemi
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6.7L I6 Cummins Diesel
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5.9L I6 Cummins Diesel
Common Problems & Known Issues

The 2008 Ram 3500 is a split-personality truck: the 6.7L Cummins variants are legendary for longevity but plagued by emissions components and killer transmission issues, while the 5.7L Hemi models suffer catastrophic engine failures from cam/lifter problems and are frankly more trouble than they're worth in this chassis.

68RFE Transmission Failure (Diesel models)

Common · high severity
Typical onset: 80,000-150,000 mi
Symptoms: Hard 2-3 or 3-4 shift flare, Transmission slipping under load or towing, Burnt ATF smell and dark fluid, Limp mode with P0841 or P0868 codes
Fix: The 68RFE behind the Cummins is chronically weak — clutch packs burn, valve body bores wear, and the overdrive drum cracks. Full rebuild with upgraded clutches and billet components takes 18-24 hours. Many owners go straight to aftermarket built units (Suncoast, etc.) to handle diesel torque properly.
Estimated cost: $3,800-6,500

Cummins 6.7L DPF/EGR System Failures

Common · medium severity
Typical onset: 60,000-120,000 mi
Symptoms: Check engine light with P2002 or P0401 codes, Frequent regen cycles cutting power, Black smoke on startup, Poor fuel economy and loss of power
Fix: The 2007.5-2009 6.7L was the first-gen emissions setup and it's a nightmare. DPF clogs, EGR coolers crack and dump coolant into exhaust, EGR valves stick. DPF replacement is 4-6 hours, EGR cooler is 8-10 hours. Many owners delete emissions (off-road only, EPA violation for street use) which solves it permanently but kills resale and legality.
Estimated cost: $1,800-4,200

5.7L Hemi Cam/Lifter Failure and Piston/Ring Issues

Occasional · high severity
Typical onset: 70,000-130,000 mi
Symptoms: Ticking/tapping noise from engine bay, Loss of power and rough idle, Excessive oil consumption (1qt per 500-1000 mi), P0300-P0308 misfire codes
Fix: The Hemi in HD trucks sees higher loads and fails harder than in cars. Cam lobes wear flat, lifters collapse, and piston rings land and burn oil like crazy. Once cam is wiped, metal debris circulates and wrecks bearings. Engine-out rebuild with new cam, lifters, rings, bearings is 30-40 hours. Shortblock replacements common. This engine was not built for this duty cycle.
Estimated cost: $6,500-11,000

Steering Linkage and Tie Rod Wear

Common · medium severity
Typical onset: 60,000-100,000 mi
Symptoms: Loose or wandering steering feel, Clunking over bumps from front end, Tire wear on inside edges, Death wobble after hitting potholes
Fix: Solid front axle with heavy-duty tie rods that still wear out — sockets get sloppy, drag link ends go bad. Track bar bushings also fail and contribute to wander. Full tie rod/drag link/track bar refresh is 3-5 hours. This is maintenance on a heavy-duty truck, not a defect, but RAM owners see it more than Ford/GM equivalents. NHTSA had multiple recalls here.
Estimated cost: $800-1,600

Transmission Oil Cooler Line Corrosion and Leaks

Occasional · medium severity
Symptoms: Red ATF puddles under truck, Low transmission fluid warnings, Transmission overheating after towing, Visible rust/corrosion on cooler lines at radiator
Fix: Steel cooler lines rust through in salt-belt states, especially where they route near the frame. Leaks start small then blow out suddenly. Line replacement is 2-4 hours depending on how much you're replacing. Auxiliary coolers help but the factory setup still corrodes. Inspect these every oil change if you live where they salt roads.
Estimated cost: $400-900

Fuel Filter/Water Separator Housing Cracking (Diesel)

Occasional · medium severity
Typical onset: 50,000-100,000 mi
Symptoms: Hard starting or long crank times, Fuel smell near driver-side frame rail, P0087 low fuel rail pressure code, Visible fuel weeping from filter housing
Fix: The factory plastic fuel filter housing on early 6.7L Cummins cracks from heat cycles and vibration. When it fails, you lose prime and suck air into the fuel system. Aftermarket billet housings are the permanent fix (AirDog, FASS). Replacement is 1-2 hours but you'll spend time bleeding air from the system. Do this proactively if you're keeping the truck.
Estimated cost: $350-700
Owner tips
  • If buying a Cummins, budget for a transmission rebuild or buy one already done — the 68RFE is a ticking time bomb under heavy use
  • Avoid the 5.7L Hemi in this chassis unless it's already had a full engine rebuild with documentation — this engine was not engineered for 3500-series duty
  • Change transmission fluid every 30k mi on diesels, not the 'lifetime fill' Chrysler claims — heat kills the 68RFE clutches
  • Inspect steering linkage annually and replace at first sign of play — death wobble is real and dangerous at highway speeds with a heavy trailer
  • For Cummins owners: install an aftermarket fuel filter/water separator setup and auxiliary transmission cooler if you tow regularly
Buy a Cummins 3500 if you can verify the transmission has been built and you're comfortable dealing with emissions headaches or deleting them; avoid the Hemi 3500 entirely unless you enjoy financing engine rebuilds.
AI-assisted summary drawn from NHTSA recall data, our labor-times database, and platform knowledge. Not a substitute for a pre-purchase inspection on a specific vehicle.
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