1994 GMC SAFARI

Typical onset: 80,000-150,000 mi

Symptoms: Coolant leaking externally at front or rear of intake manifold, White smoke from exhaust on cold start, Coolant mixing with oil (milky dipstick), Rough idle and misfire codes after coolant intrusion into cylinders

Fix: Replace both upper and lower intake gaskets, new coolant. Critical to use updated Fel-Pro composite gaskets, not OEM plastic-framed style that fails. 6-8 labor hours. If coolant contaminated oil, expect additional bearing/piston damage requiring engine rebuild.

Estimated cost: $800-1,200

Typical onset: 90,000-140,000 mi

Symptoms: Transmission fluid leaking at radiator connections or along steel lines, Transmission overheating, slipping, delayed engagement, Pink milkshake in coolant overflow (cooler ruptured inside radiator), Harsh shifts or no forward gears after overheating

Fix: Factory setup uses inadequate radiator-mounted cooler. Lines rust through at bends near subframe. Proper fix: replace all cooler lines, add external auxiliary transmission cooler, flush both systems. If cooler ruptured into radiator, transmission rebuild usually required (4-6 hours for lines/cooler, 12-16 hours if trans rebuild needed).

Estimated cost: $400-700 (lines/cooler only), $2,200-3,500 (with transmission rebuild)

Typical onset: 120,000-180,000 mi

Symptoms: No 3rd or 4th gear (stuck in 2nd gear), Flare or slip on 2-3 or 3-4 upshift, Check engine light with P0735 or P0740 codes, Burnt transmission fluid smell

Fix: 4L60E is weak in 3-4 clutch pack in high-mileage applications, especially in loaded vans. Requires transmission removal, disassembly, replacement of 3-4 clutches, often pressure regulator valve and pump. 10-14 labor hours. Preventive: change fluid/filter every 30,000 miles.

Estimated cost: $1,800-2,800

Typical onset: 60,000-120,000 mi

Symptoms: No-start or intermittent stalling when hot, Rough running, hesitation, bucking under load, Crossfire between cylinders (cap carbon tracking), Dies after 20-30 minutes running, restarts when cool

Fix: Vortec distributor caps crack internally, rotors burn through. Ignition control module (under distributor) fails when heat-soaked. Replace cap, rotor, wires as set; test module with heat. Module replacement requires distributor removal. 1.5-2.5 labor hours.

Estimated cost: $250-450

Typical onset: 100,000-160,000 mi

Symptoms: Hard start or long crank, especially when hot, Intermittent stalling at highway speed, Loss of power under acceleration, Fuel pressure drops below 55 psi (should be 60-66 psi)

Fix: In-tank electric pump. Safari requires removing fuel tank (not accessible through cab). Check fuel filter first (often clogged by 80k). Pump replacement: 3-4 labor hours. Use AC Delco or equivalent OEM-quality pump.

Estimated cost: $500-750

Typical onset: 120,000+ mi

Symptoms: Oil dripping from bell housing area or rear of oil pan, Oil spots on driveway after overnight parking, Low oil level between changes

Fix: Two-piece rear main seal leaks at high mileage. Oil pan gasket also seeps due to corrosion of steel pan. Rear main requires transmission removal (8-10 hours). Oil pan: 2-3 hours. Often done together if transmission is out for other work.

Estimated cost: $400-650 (oil pan only), $1,200-1,600 (rear main with trans removal)

Typical onset: 70,000+ mi

Symptoms: ABS warning light on dash, No ABS function (normal braking works), Codes for rear wheel speed sensor circuit, Sensor wire corroded at rear axle

Fix: Rear sensors mounted on differential cover corrode in rust-belt climates. Connector and wiring often need repair or replacement. 1-1.5 labor hours per side. Not safety-critical but ABS non-functional.

Estimated cost: $180-320