1998 CHEVROLET BLAZER

Typical onset: 80,000-150,000 mi

Symptoms: External coolant leaks at front or rear of intake, Coolant mixing into oil creating strawberry milkshake in oil cap, Overheating, Rough idle or misfire from coolant entering cylinders, White smoke from exhaust

Fix: Requires complete upper intake removal, gasket replacement with updated composite gaskets (NOT original plastic), coolant flush, and often oil change. Critical to replace with aluminum coolant elbows at same time. 6-8 hours labor. If caught late with coolant in oil, expect bearing damage requiring full engine rebuild.

Estimated cost: $800-1,200 for gaskets alone; $3,500-5,500 if engine damage occurred

Typical onset: 100,000-180,000 mi

Symptoms: Pink milkshake in coolant reservoir (trans fluid in coolant), Transmission slipping or delayed engagement, Overheating transmission, Coolant loss with no external leaks, Transmission failure within days of contamination

Fix: Steel cooler lines rust through inside radiator end tanks, allowing coolant and ATF to mix. Once mixed, transmission is typically destroyed. Requires radiator replacement, all cooler lines, transmission flush or rebuild, and complete coolant system flush. Preventive replacement of lines at 100k saves the trans. 8-12 hours if trans survives; 16-20+ for trans rebuild.

Estimated cost: $400-700 preventive line/radiator replacement; $2,800-4,500 with transmission rebuild

Typical onset: 70,000-120,000 mi

Symptoms: Clunking over bumps from front end, Steering wander or pull, Uneven tire wear on inside edge, Visible play when prying on tire at 6 and 12 o'clock, Catastrophic separation causing wheel to fold under (rare but documented)

Fix: Press-in lower ball joints wear prematurely and can fail without warning. GM recalled some years but not 1998 comprehensively. Requires control arm removal, ball joint press-out and replacement, alignment. Many techs recommend replacing entire lower control arms with better aftermarket units. 3-4 hours per side. SAFETY CRITICAL - inspect every oil change after 60k.

Estimated cost: $400-600 per side for ball joints; $600-900 per side for complete control arm replacement

Typical onset: 120,000-180,000 mi

Symptoms: No-start condition with cranking, Stalling when hot, Loss of power under load, Whining noise from fuel tank, Hard starting requiring multiple key cycles

Fix: In-tank fuel pump assembly fails, requiring tank drop. Common issue but not as universal as intake gaskets. Often the pump motor itself, sometimes the sending unit. 2-3 hours labor. Replace fuel filter at same time (often neglected and contributes to pump death).

Estimated cost: $500-800

Typical onset: 150,000-200,000 mi

Symptoms: Slipping on 2-3 shift, Delayed engagement into drive or reverse, Harsh or flare shifts, No 4th gear (overdrive), Check engine light with trans codes

Fix: The 4L60E behind the 4.3L is marginal in this application. Even without cooler line contamination, expect 3-4 clutch pack wear, torque converter shudder, and solenoid failures. Full rebuild includes clutches, bands, solenoids, torque converter, and updated separator plate. 10-14 hours labor for R&R and rebuild.

Estimated cost: $2,200-3,500

Typical onset: 60,000-100,000 mi

Symptoms: Hard starting in damp weather, Random misfires, Rough idle, Stalling, Check engine light with misfire codes

Fix: The Vortec uses a distributor with cap/rotor that cracks and carbon-tracks, plus the Central Sequential Fuel Injection (CSFI) spider under the intake is known for leaking. Cap/rotor is 1 hour; spider injector requires intake removal similar to gaskets (6-8 hours) and is often done simultaneously with intake gaskets to save labor.

Estimated cost: $80-150 for cap/rotor; $800-1,200 for spider injector with intake gaskets

Typical onset: 90,000-140,000 mi

Symptoms: Black smoke on startup, Rough running when cold, Fuel smell in oil, Hard starting after sitting, Raw fuel dripping from throttle body

Fix: The fuel pressure regulator on the CSFI spider fails, dumping raw fuel into the intake manifold and potentially into crankcase. Creates dangerous rich condition and dilutes oil. Requires intake removal and spider injector assembly replacement. 6-8 hours labor, same job as spider injector or intake gaskets.

Estimated cost: $700-1,100