1965 BUICK SKYLARK

Typical onset: original mounts typically failed by 50,000-80,000 mi; replacements degrade every 10-15 years regardless of miles

Symptoms: Clunking when shifting into drive or reverse, Excessive vibration at idle, especially with A/C on, Visible engine movement when revving in park, Transmission shifter feels loose or notchy

Fix: Replace all three mounts (two engine, one transmission). Requires lifting engine slightly with jack and wood block. 2-3 hours labor for experienced tech, 4-5 for DIY first-timer. Original-style rubber mounts are available but polyurethane upgrades reduce NVH.

Estimated cost: $300-600

Typical onset: 80,000-150,000 mi on original builds; earlier if neglected or overheated

Symptoms: Heavy metallic knocking from lower engine, worse under load, Oil pressure dropping below 10 psi at hot idle, Blue smoke on startup and deceleration (ring wear), Metal shavings or glitter in oil pan, Excessive crankcase blowby visible at oil filler

Fix: Requires engine removal and complete lower end rebuild: crank inspection/machining, all main and rod bearings, piston rings minimum. Often becomes full rebuild once open due to cylinder ridge wear and cam condition. Engine R&R is 8-12 hours; machine work adds 1-2 weeks. Total shop time 20-30 hours including reassembly.

Estimated cost: $3,500-6,500

Typical onset: transmission fluid never changed: failure by 60,000-90,000 mi; with maintenance: 100,000+ mi possible

Symptoms: Slipping between gears or no engagement in reverse, Delayed engagement (more than 2 seconds into drive), Burnt transmission fluid smell, dark brown or black fluid, Whining or grinding noise in gear

Fix: Transmission removal and rebuild or replacement. These units are simpler than later automatics but parts availability varies. R&R is 6-8 hours; rebuild adds 8-12 hours. Cooler line inspection/replacement essential during this job—corroded lines cause repeat failures.

Estimated cost: $1,800-3,200

Symptoms: Hard starting when hot or after sitting, Stumbling or dying at idle after 10-15 minutes running, Fuel smell inside cabin or near tank, Visible rust particles in fuel filter, Engine starvation under acceleration or at highway speed

Fix: Typically requires fuel tank removal, cleaning or replacement, new sending unit, replacement of all rubber fuel lines (original lines harden and crack internally), inline filter, and mechanical fuel pump rebuild or replacement. Tank R&R is 3-4 hours, complete fuel system refresh is 6-9 hours total.

Estimated cost: $800-1,600

Typical onset: balancer deteriorates by 40,000-70,000 mi; inherent design vibration present always

Symptoms: Pronounced vibration at all RPM ranges, especially 1,500-2,500 RPM, Harmonic balancer visibly wobbling or rubber ring separating, Crankshaft pulley bolt loosening repeatedly, Accelerated wear on engine accessories (alternator bearings, water pump)

Fix: Replace harmonic balancer (1.5-2 hours) and inspect for crankshaft snout damage from wobble. This odd-fire engine design creates inherent imbalance that aftermarket balancers only partially address. Consider engine swap to 300ci or 340ci V8 for smoother operation if doing major work anyway.

Estimated cost: $250-500

Typical onset: develops gradually, noticeable by 60,000-100,000 mi

Symptoms: Oil puddle under rear of engine after sitting overnight, Oil coating on bellhousing and starter, Transmission bellhousing wet inside with oil, Low oil level requiring frequent top-ups (1 quart per 500-800 miles)

Fix: Rear main seal requires transmission removal (6-8 hours labor). Often done during clutch replacement on manuals or transmission rebuild on automatics to justify labor. Oil pan gasket is 3-4 hours with exhaust removal. Most techs recommend doing both if transmission is already out.

Estimated cost: $600-1,400