1974 PONTIAC TEMPEST

Typical onset: 80,000-120,000 mi

Symptoms: Slipping on 1-2 or 2-3 shift under load, Delayed engagement when shifting to Drive or Reverse, Burnt transmission fluid smell, dark brown or black fluid, Whining or grinding noise in gear

Fix: Full rebuild required in most cases, 8-12 hours labor. Cooler lines and external cooler inspection critical—many failures start with overheating from clogged factory cooler. Kit plus labor runs high, but these units rebuild well with upgraded clutches and bands.

Estimated cost: $1,800-3,200

Typical onset: 90,000-140,000 mi

Symptoms: Rattling noise on cold start that quiets after warmup, Rough idle or stumbling, especially when warm, Check timing and it's retarded 8-12 degrees from spec, Poor fuel economy and lack of power

Fix: Pontiac V8s eat timing sets, especially with irregular oil changes. Requires front cover removal, 6-8 hours labor. Replace with double-roller set and new oil pump while you're in there. I6 and Chevy small-blocks less prone but still check at 100k.

Estimated cost: $800-1,400

Symptoms: Hesitation or bog on acceleration, Hard starting when warm, flooding, Black smoke from exhaust, poor fuel economy, Fuel leaking from base or accelerator pump

Fix: Rochester Quadrajets are excellent when tuned but suffer from ethanol fuel degradation, warped throttle shafts, and dried-out accelerator pump cups. Rebuild kits are cheap but expect 3-5 hours for proper disassembly, cleaning, and calibration. Many shops just swap on a Holley or Edelbrock instead.

Estimated cost: $350-700

Symptoms: Running hot in traffic or on highway, Coolant leaking from lower seam or end tanks, Green or orange residue on radiator face, Steam from under hood after shutdown

Fix: Original copper-brass radiators are 50 years old and internally clogged or externally corroded. Budget 2-3 hours for R&R, but 455 cars especially need upgraded 4-row aluminum or you'll chase overheating forever. Water pump and hoses should be done simultaneously—these aren't separate jobs on a car this old.

Estimated cost: $600-1,200

Typical onset: 100,000+ mi

Symptoms: Oil spot under center/rear of engine after sitting overnight, Oil coating on bellhousing or transmission, Low oil level despite no visible external leaks up front, Clutch slipping if manual transmission (oil-soaked disc)

Fix: Rear main seal on Pontiac V8s is a rope-style two-piece design—leak is almost guaranteed by now. Requires transmission removal, 6-8 hours labor. Oil pan gasket leaks are easier (4 hours) but often diagnosed incorrectly when rear main is the real culprit. Drop the pan anyway and check for sludge—tells you about prior maintenance.

Estimated cost: $700-1,400

Typical onset: 70,000-110,000 mi

Symptoms: Miss or stumble at highway speeds under load, Erratic idle, surging, Difficult starting, requires multiple cranks, Points burn rapidly, condenser failures

Fix: Factory points distributors have worn bushings and shafts by now, causing timing scatter and weak spark. Aftermarket HEI conversion (Pontiac V8) or electronic ignition (I6/Chevy engines) is the right fix, 2-3 hours including tuning. Bandaid fixes with new points only last 5,000 miles.

Estimated cost: $400-800

Symptoms: Clunking or squeaking over bumps, body feels loose, Doors don't align or close properly, Visible rust perforation on frame rails behind front wheels, Sagging rear quarter panels or trunk floor

Fix: Rust-belt cars have severe frame rot in rocker areas and rear frame kick-ups. Body mounts rot out on all of them. If caught early, body mounts are 4-6 hours; frame repair is specialty welding work and structural nightmare. Inspect thoroughly before buying—this can total an otherwise solid car.

Estimated cost: $500-3,000+