1983 BUICK REGAL

Typical onset: 80,000-120,000 mi

Symptoms: Slipping on 3-4 upshift or won't hold overdrive, Delayed engagement into Drive or Reverse, Metal shavings in pan during fluid change, Whining noise in overdrive that goes away when locked out

Fix: Full rebuild required—this transmission was underbuilt for the V8 torque. Expect 12-16 hours labor for R&R and rebuild. Upgraded aftermarket clutch packs and accumulator springs recommended if keeping a V8. Many owners swap to TH350 non-overdrive for durability.

Estimated cost: $1,800-2,800

Typical onset: 60,000-100,000 mi

Symptoms: White smoke on startup that doesn't clear, Excessive blowby from oil fill cap, Loss of compression in multiple cylinders, Coolant mixing with oil—milky dipstick

Fix: The 5.7L Oldsmobile diesel has catastrophic head gasket and block cracking issues—GM used gasoline engine architecture without proper reinforcement. Most techs recommend complete engine swap to gas 305 or 350 rather than rebuild. Diesel rebuild runs 40-50 hours, gas swap is 18-24 hours.

Estimated cost: $3,500-5,500

Symptoms: Visible rust perforation at rear wheel wells and quarter panels, Body separation at door gaps—doors won't align properly, Clunking over bumps from deteriorated body mount bushings, Sagging rear end or twisted body shell

Fix: G-body frames rust at rear subframe mounts and body mounts rot out completely. Body mount replacement is 6-8 hours for all mounts. Frame rust requires welding repairs or replacement sections—varies widely by damage. Surface rust is manageable, but structural rust is expensive.

Estimated cost: $800-2,500

Typical onset: 70,000-110,000 mi

Symptoms: Rough idle and stalling when cold, Hesitation on acceleration or flat spot at part-throttle, Hard starting after sitting—fuel evaporates from bowl, Black smoke and poor fuel economy—running rich

Fix: The computer-controlled Quadrajet needs full rebuild at this age—internal gaskets, accelerator pump, needle/seat, and choke pull-off. DIY rebuild kits run 4-6 hours for someone experienced. Many owners convert to Edelbrock or Holley to eliminate computer-controlled choke and mixture control.

Estimated cost: $350-700

Typical onset: 90,000-140,000 mi

Symptoms: Oil spots on driveway after sitting overnight, Oil accumulation on bottom of bellhousing, Visible seepage at oil pan rail—more pronounced at corners, Wet oil film on back of engine block

Fix: The two-piece rear main seal hardens and leaks eventually. Rear main requires transmission removal—8-10 hours labor. Oil pan is easier at 3-4 hours but requires exhaust removal and motor mounts loosened to lift engine. Both are deferred maintenance items until leaks become severe—a quart every 500 miles.

Estimated cost: $650-1,200

Typical onset: 80,000-130,000 mi

Symptoms: Whining noise when turning wheel, especially when cold, Puddle of red ATF under front of car, Intermittent heavy steering or wandering, Low fluid level despite regular top-offs

Fix: Saginall pump seals fail and gear box develops input shaft seal leaks. Pump replacement is 2 hours, gear box is 3-4 hours. Hoses also crack and weep. Address all three at once if gear box is leaking—no point doing twice. OE-quality parts are still available and affordable.

Estimated cost: $400-850