The 1982 Buick Regal sits on GM's G-body platform with a mix of reliable small-blocks and the notorious 350 diesel. Bodies rust aggressively in the rocker/quarter areas, and the TH200-4R transmission is the Achilles heel for V8-equipped cars.
TH200-4R Transmission Failure (V8 models)
Common · high severityTypical onset: 80,000-130,000 mi
Symptoms: Slipping on 2-3 upshift under load, No fourth gear overdrive engagement, Harsh downshifts or delayed engagement from Park, Metal shavings in pan, burnt fluid smell
Fix: The TH200-4R was undersized for the 305/350 V8 torque. Rebuild with hardened input drum, upgraded clutches, and valve body mods runs 12-16 hours labor. Many shops recommend swapping to a TH350 non-overdrive for reliability, adding custom driveshaft work.
Estimated cost: $1,800-3,200
Oldsmobile 350 Diesel Engine Catastrophic Failure
Common · high severityTypical onset: 60,000-100,000 mi
Symptoms: White smoke from exhaust, coolant loss with no external leaks, Hard starting when warm, excessive blowby, Cracked cylinder heads between valve seats, Head gasket failure, water in oil pan
Fix: GM converted a gas 350 to diesel without adequate reinforcement. Head bolt design allows heads to lift and crack. Most need complete engine rebuild or replacement—heads, block machining, injection pump, glow plug system. Figure 35-45 hours labor for proper rebuild with upgraded ARP studs.
Estimated cost: $4,500-7,500
Body Rust—Rockers, Rear Quarters, Trunk Floor
Common · medium severitySymptoms: Visible rust bubbling along rocker panels below doors, Trunk floor soft spots or holes near wheelwells, Rear quarter panel rust behind wheel opening, especially driver side, Door bottoms rotting from inside out
Fix: G-body rockers and quarters trap moisture and salt. Proper repair requires cutting out metal, welding patch panels or full quarter skins. Rockers alone take 8-12 hours per side; full quarter panel replacement runs 18-24 hours. Many cars have Bondo over structural rust—magnet test before buying.
Estimated cost: $1,200-4,000
Carburetor Issues (231 V6 and 305 V8)
Common · low severityTypical onset: 70,000-120,000 mi
Symptoms: Rough idle, stalling at stoplights when warm, Hesitation on acceleration, black smoke, Fuel smell in cabin, leaking accelerator pump or float bowl, Computer Command Control codes for rich/lean mixture
Fix: Rochester E4ME and E4MC carbs have vacuum leaks in the base gasket, worn throttle shafts, and deteriorated rubber components. Most shops rebuild the carb (4-6 hours) or swap in a remanufactured unit. The Computer Command Control system adds diagnosis complexity—many techs delete it for a conventional carb.
Estimated cost: $450-900
Rear Main Seal Leak (All Engines)
Occasional · medium severityTypical onset: 90,000-150,000 mi
Symptoms: Oil drips from bellhousing onto crossmember, Oil accumulation on transmission pan or exhaust, Gradual oil consumption without visible external leaks elsewhere
Fix: Two-piece rope seal hardens and shrinks with age. Requires transmission removal—8-12 hours labor depending on V6 or V8. One-piece conversion seal kits are available and preferred. Often discovered during transmission work, so many owners defer until trans is out for other reasons.
Estimated cost: $600-1,100
Front Suspension Worn Bushings and Ball Joints
Common · medium severityTypical onset: 80,000-130,000 mi
Symptoms: Clunking over bumps, wandering on highway, Uneven tire wear on inside edge, Play in steering wheel with wheels straight, Failing alignment checks, camber/caster out of spec
Fix: G-body control arm bushings deteriorate and upper/lower ball joints wear. Typical job replaces both uppers, both lowers, and control arm bushings—takes 6-8 hours. Alignment required afterward. Many cars also need idler and pitman arms for tight steering.
Estimated cost: $800-1,400
Buy a clean V6 or small-block V8 car with solid floors and service records—skip the diesel and any G-body with visible rust.
AI-assisted summary drawn from NHTSA recall data, our labor-times database, and platform knowledge. Not a substitute for a pre-purchase inspection on a specific vehicle.