2001 GMC JIMMY

Typical onset: 80,000-130,000 mi

Symptoms: Coolant leaking externally around intake valley or into oil (milky dipstick), Overheating or steady coolant loss without visible external leaks, Rough idle or misfires from coolant seeping into cylinders, Check engine light with random misfire codes

Fix: Replace lower intake gaskets (Fel-Pro or equivalent), flush coolant, inspect distributor and upper plenum. Often done with upper gaskets, thermostat, and coolant elbows while you're in there. 6-8 labor hours for thorough job.

Estimated cost: $800-1,400

Typical onset: 100,000-150,000 mi

Symptoms: Transmission fluid pooling under vehicle, often passenger side near radiator, Low transmission fluid on dipstick, slipping or delayed engagement, Rust-through on steel cooler lines where they connect to radiator, Possible coolant contamination in trans fluid if internal radiator cooler fails

Fix: Replace corroded steel cooler lines with pre-bent or custom bent lines, replace rubber hoses at connections. If radiator internal cooler failed, replace radiator and flush transmission completely. 2-3 hours for lines alone, 5-7 if trans contamination occurred requiring flush and filter service.

Estimated cost: $400-1,200

Typical onset: 120,000-180,000 mi

Symptoms: Slipping on 2-3 shift or no 3rd/4th gear engagement, Harsh or delayed shifts, especially when warm, Check engine light with P0733 (3rd gear incorrect ratio), Burnt transmission fluid smell, dark or metallic fluid

Fix: Rebuild or replace 4L60E transmission. Common internal failure is 3-4 clutch pack. Rebuild includes new clutches, bands, seals, filter, and fluid. 8-12 labor hours for R&R and rebuild, or swap with reman unit.

Estimated cost: $1,800-3,200

Typical onset: 150,000-200,000 mi

Symptoms: Excessive oil consumption (quart every 500-1,000 miles), Blue smoke from exhaust on startup or acceleration, Loss of compression in one or more cylinders, Fouled spark plugs, misfires under load

Fix: Engine rebuild or replacement required. Full teardown for rings, hone cylinders, new bearings, gaskets. Some opt for reman or junkyard replacement motor. 18-24 labor hours for in-chassis rebuild, 12-16 for engine swap.

Estimated cost: $2,500-4,500

Typical onset: 90,000-140,000 mi

Symptoms: Service 4WD light illuminated on dash, Inability to engage or disengage 4WD, stuck in 2WD or 4WD, Grinding or clicking from transfer case when attempting shift, Intermittent 4WD function or delay in engagement

Fix: Replace transfer case encoder motor and/or selector switch on dash. Sometimes requires resealing transfer case if internal mode fork is damaged. 2-3 hours for encoder motor, 6-8 if case needs opening.

Estimated cost: $300-900

Typical onset: 100,000-150,000 mi

Symptoms: No-start condition with crank but no fuel pressure, Stalling or sputtering under load or when fuel tank is low, Whining noise from rear of vehicle near fuel tank, Check engine light with fuel trim or fuel system codes

Fix: Drop fuel tank, replace fuel pump module assembly including strainer and sending unit. Replace fuel filter at same time. 3-4 labor hours.

Estimated cost: $500-800

Symptoms: Brake lights inoperative or stuck on, Cruise control won't engage or disengage, Transmission won't shift out of Park intermittently, Check for open recall campaign 03V266000 or 03V355000

Fix: Replace brake light switch on pedal assembly. GM issued recalls for defective switches. 0.5-1 labor hour, often covered under recall if VIN eligible.

Estimated cost: $80-150