1991 DODGE W250

Typical onset: 80,000-150,000 mi

Symptoms: Slipping between gears, especially 2nd to 3rd, Delayed engagement when shifting into Drive or Reverse, Burnt transmission fluid smell, Overheating indicated by fluid discoloration

Fix: The 727/518 automatics weren't built for Cummins torque. Expect full rebuild or replacement. Rebuild takes 12-16 hours including R&R. Upgrade to billet components and add aftermarket trans cooler during rebuild to prevent repeat failure.

Estimated cost: $2,200-3,800

Typical onset: 120,000-180,000 mi

Symptoms: Low-frequency knocking at idle that increases with RPM, Metallic rattling on cold starts, Sudden loss of oil pressure, Metal flakes/shavings in oil

Fix: The 360 V8 has soft bearing material and marginal oiling under load. Rod knock means full teardown. Most shops recommend short block replacement or complete rebuild with hardened bearings. Plan 24-30 hours labor for engine removal, disassembly, machine work coordination, and reassembly.

Estimated cost: $3,500-5,500

Typical onset: 60,000-120,000 mi

Symptoms: Hard starting especially when warm, Loss of power under load or at highway speeds, Excessive white smoke on startup, Engine stalling after running fine for 15-20 minutes

Fix: The mechanical lift pump on the Cummins fails and sends debris into the injection pump. Replace lift pump, fuel filter, and drain tank. If caught early, 2-3 hours. If injection pump is damaged, add 6-8 hours and $800-1,200 for a rebuilt P-pump.

Estimated cost: $350-2,000

Symptoms: Inability to shift into or out of 4WD, Grinding when attempting to engage 4WD, Shifter feels loose or won't stay in position, Pops out of 4-Low under load

Fix: Worn shift fork, detent springs, or linkage bushings. External linkage adjustment sometimes helps temporarily but typically needs internal work. Transfer case R&R and rebuild takes 6-8 hours. NP205 is cast iron and more durable but heavier.

Estimated cost: $800-1,400

Typical onset: 100,000-160,000 mi

Symptoms: Clunking when shifting from Park to Drive/Reverse, Excessive driveline vibration at highway speeds, Visible sagging of transmission tailhousing, Transmission hits crossmember on hard acceleration

Fix: The rubber mount deteriorates and the crossmember cracks from heavy towing. Diesel models especially. Replace mount and inspect crossmember for cracks; welding reinforcement is common. 2-3 hours with proper jack support.

Estimated cost: $250-500

Symptoms: Visible rust holes in cab corners behind doors, Soft spots in floor under carpet/mat, Rust perforation in bed floor and fenders, Water leaking into cab during rain

Fix: More prevalent in salt states. Surface rust becomes structural failure. Cab corner replacement panels available but labor-intensive (8-12 hours per side with bodywork). Bed floor patch panels need welding and undercoating. Not a breakdown issue but kills resale value.

Estimated cost: $1,200-3,500