1989 PONTIAC 6000

Typical onset: 80,000-140,000 mi

Symptoms: Slipping between 2nd and 3rd gear under moderate throttle, Delayed engagement when shifting from Park to Drive, Shuddering or hunting during highway cruise, Metal shavings visible in pan during fluid changes, Complete loss of forward gears leaving you stranded

Fix: Full rebuild required in most cases — this transmission doesn't fail gracefully. Expect 8-12 hours labor for R&R and rebuild. The 440-T4 has weak apply pistons and inadequate clutch packs from the factory. Band adjustments buy you maybe 5,000 miles if you catch it early. Cooler line failures accelerate the death spiral.

Estimated cost: $1,800-2,800

Typical onset: 120,000-180,000 mi

Symptoms: Deep knocking or rattling from crankcase that worsens with RPM, Low oil pressure at idle (under 10 psi) despite recent oil change, Metallic debris in oil filter media, Sudden catastrophic failure with connecting rod punching through block

Fix: Main and rod bearings wear prematurely on these engines, especially if oil changes were stretched past 5,000 miles. Once knocking starts, you're looking at minimum 18-24 hours for full teardown, machine work (crank polishing), and reassembly. Many shops quote engine replacement instead since used 2.8L cores are cheap. The 3.1L is marginally better but not immune.

Estimated cost: $2,200-3,800

Typical onset: 70,000-110,000 mi

Symptoms: Clunking when shifting from Reverse to Drive, Excessive vibration at idle in Drive, Visible sagging of transmission tail when inspected on lift, Transmission shift linkage feels sloppy or imprecise

Fix: The rubber mounts collapse and the stamped steel crossmember cracks near the mount bosses. Not a hard job — 1.5-2.5 hours — but neglecting it accelerates transmission cooler line failure and exhaust hanger stress. Replace both mounts and inspect crossmember for cracks requiring welding or replacement.

Estimated cost: $250-450

Typical onset: 90,000-140,000 mi

Symptoms: Coolant seeping externally around intake manifold perimeter, White smoke from tailpipe during cold starts, Gradual coolant loss with no visible external leaks, Rough idle and misfire when coolant enters cylinders, Milky residue in valve covers if severely neglected

Fix: GM's composite intake gaskets from this era deteriorate predictably. The lower gasket fails more often, leaking coolant into the valley and sometimes into cylinders. Job requires intake removal, careful cleaning of old gasket material, and replacement with updated Felpro or OEM gaskets. Budget 4-6 hours labor. Catch it early before it hydrolocks a cylinder.

Estimated cost: $450-750

Symptoms: Hard starting after sitting overnight, Stumbling and hesitation during acceleration, Stalling at stoplights after highway driving, Check Engine Light with lean codes (if OBD-I scanner available)

Fix: These cars used TBI fuel injection with in-tank pumps that don't tolerate old fuel well. If the car sat for months or was filled with questionable gas, varnish clogs the filter and injector screens. Replace fuel filter (30 minutes), drop tank and clean if necessary (add 2-3 hours), and run injector cleaner. Pump replacement adds another $400-600 if it's weak.

Estimated cost: $120-650

Typical onset: 100,000-150,000 mi

Symptoms: Squealing from front of engine that worsens with steering input, Heavy steering effort intermittently or constantly, Burning rubber smell from serpentine belt slipping on seized pulley, Serpentine belt shredding or throwing off

Fix: The press-fit pulley on the P-series pump seizes to the shaft from corrosion. Sometimes the pump itself is fine but the pulley won't spin. Replacement pumps are cheap and plentiful — 1.5-2 hours labor including belt and fluid flush. Don't ignore the squeal or you'll strand yourself when the belt comes off.

Estimated cost: $220-380