1990 ISUZU RODEO

Typical onset: 80,000-140,000 mi

Symptoms: White smoke from exhaust, especially on cold start, Coolant loss with no visible leaks, Overheating under load or at highway speeds, Milky oil on dipstick or oil cap, Rough idle and misfires as coolant enters cylinders

Fix: Head gasket job alone is 12-16 hours with both heads off, resurfacing required. Problem is many owners ignore early symptoms and overheat repeatedly, warping heads or damaging pistons/rings. At that point you're looking at a full rebuild with new pistons, rings, bearings, and machine work. Short-block replacement is 20-25 hours if core damage is severe.

Estimated cost: $1,800-3,200 for gaskets alone, $4,500-7,500 for full rebuild

Typical onset: 70,000-120,000 mi

Symptoms: Transmission fluid puddling under vehicle, usually front-center, Burnt transmission fluid smell, Slipping gears or delayed engagement after fluid loss, Rusty, corroded hard lines visible along frame rail

Fix: Steel cooler lines rust through where they run along the frame. Replacement involves dropping lines, flaring new tubing or using pre-bent aftermarket lines if available. Figure 3-5 hours including fluid refill and leak check. If transmission ran low on fluid before noticed, expect internal damage and eventual rebuild.

Estimated cost: $350-650 for lines and labor, add $1,800-2,800 if transmission needs rebuild

Typical onset: 90,000-150,000 mi

Symptoms: Clunking when shifting from park to drive or reverse, Excessive driveline vibration, especially under acceleration, Visible sag or torn rubber on mount during inspection

Fix: Rubber transmission mount deteriorates and allows excessive movement. Need to support transmission with jack, unbolt old mount, install new. About 1.5-2 hours. Often done alongside engine mounts which fail similarly.

Estimated cost: $180-320

Symptoms: Hard starting, especially when hot, Loss of power under load or at highway speeds, Stalling or sputtering during acceleration, Check engine light with lean codes

Fix: Inline fuel filter clogs from sediment, especially if tank hasn't been cleaned or vehicle sat. Filter replacement is 0.5 hours, but often reveals bigger issue—fuel pump weakening or tank full of rust. If pump is failing, expect 2-3 hours to drop tank and replace pump assembly.

Estimated cost: $80-150 for filter, $450-750 if pump replacement needed

Typical onset: 120,000-180,000 mi

Symptoms: Knocking noise from lower engine, louder when cold, Low oil pressure at idle, especially when warm, Metallic debris in oil during changes, Vibration felt through entire vehicle

Fix: If head gasket failure caused severe overheating, crankshaft can warp slightly and main/rod bearings get damaged. Diagnosis requires dropping oil pan (4-5 hours) and measuring clearances. Full crank R&R and bearing replacement is 18-22 hours, requires machine shop for journal polishing or grinding. Many techs opt for used or remanufactured short-block swap instead at this point.

Estimated cost: $3,500-6,000 depending on crank condition and parts sourcing

Symptoms: Radiator and heater core clogged with rust and sludge, Water pump leaking from weep hole, Thermostat sticking closed causing rapid overheating, Radiator cap failing to hold pressure

Fix: This isn't a single part failure but a pattern: owners skip coolant changes and the system corrodes internally. By the time you see problems, it's often too late—head gaskets are already compromised. Full cooling system overhaul (radiator, water pump, thermostat, hoses, flush) is 6-8 hours but only worthwhile if engine hasn't been damaged yet.

Estimated cost: $800-1,400 for complete system refresh