1967 BUICK LESABRE

Typical onset: any mileage on original cooler

Symptoms: Transmission fluid in radiator or coolant in transmission pan, Pink or milky fluid on dipstick, Sudden transmission slip or no engagement after coolant contamination, External fluid weeping at steel cooler lines near frame rails

Fix: Replace external cooler or radiator if integral type; flush transmission thoroughly, replace filter and pan gasket, refill with Dexron. If contamination occurred, expect internal transmission damage requiring rebuild. Steel cooler lines rust through at bends—replace with pre-bent or NiCopp. 4-6 hours labor for cooler/lines; 12-16 hours if transmission rebuild needed.

Estimated cost: $600-1,200 for cooler and lines; $2,200-3,800 if transmission rebuild required

Typical onset: 80,000-150,000 mi

Symptoms: Blue smoke on startup or acceleration, Using a quart of oil every 500-800 miles, Fouled spark plugs in one or more cylinders, Low cranking compression (under 120 psi)

Fix: Nailhead engines (340, 400, 430) have vertical valves and narrow piston ring lands that wear rapidly if oil changes were skipped. Requires full teardown, bore and hone (often .030 over), new pistons and rings, rod and main bearings, timing chain, and gaskets. Heads may need valve job. 18-24 hours labor for in-car short block rebuild; 26-32 hours for complete engine-out rebuild.

Estimated cost: $2,800-4,500 short block; $4,200-6,500 complete rebuild

Symptoms: Fuel odor in garage or driveway after sitting, Hard starting when hot, Black smoke and rich running, Flooding over into intake manifold or air cleaner

Fix: Rochester 2GC or 4GC carbs have cork or rubber floats and old viton seals that fail with modern ethanol fuel. Rebuild with ethanol-compatible kit, set float level precisely, check needle and seat. If carburetor body is warped from heat, replacement may be necessary. 2-3 hours labor for on-car rebuild; budget for core replacement if body is damaged.

Estimated cost: $350-650 rebuild; $600-950 with replacement carburetor

Typical onset: any age, worsens over time

Symptoms: Oil puddle under back of engine after sitting, Wet bellhousing or transmission front face, Oil saturation on clutch (if manual, rare on LeSabre) or flywheel

Fix: Original rope-type rear main seals harden and shrink over decades. Can sometimes be replaced with engine in car by dropping oil pan and rear cap (tricky on Nailhead due to cap bolt access), but proper fix requires transmission removal. 6-8 hours labor in-car method; 10-12 hours if transmission must come out for access. Modern split-lip seals available but require machined groove in some cases.

Estimated cost: $650-1,100

Symptoms: Clunk when shifting into drive or reverse, Vibration at idle in gear, Transmission tail shaft visibly sagging, Driveshaft angle excessive, causing U-joint binding

Fix: Rubber transmission mounts collapse after 50+ years; crossmember itself can rust or crack at mounting points on these full-frame cars. Replace mount and inspect crossmember for integrity; reinforce or replace if cracked. 1.5-2.5 hours labor if crossmember is sound; add 2-3 hours if welding or replacement needed.

Estimated cost: $220-450 mount only; $600-950 with crossmember work

Typical onset: 100,000+ mi or after prolonged sitting

Symptoms: Fuel pump clicking or rattling noise, Loss of fuel pressure, engine starves at speed, New fuel pump fails repeatedly in short order

Fix: Mechanical fuel pump runs off an eccentric on the camshaft via a pushrod. Pushrod wears a groove or eccentric wears flat, causing weak or erratic pumping. Requires timing cover removal to inspect and replace pushrod and eccentric (if cam replacement not done). If caught early, pushrod replacement alone may suffice (2-3 hours); if eccentric is damaged, timing chain replacement and possibly cam work needed (8-12 hours).

Estimated cost: $350-600 pushrod only; $1,200-2,200 with timing set and eccentric