1991 GMC G3500

Introduction to the 1991 GMC G3500

The 1991 GMC G3500 is a heavy-duty pickup truck that offers several engine and transmission options. The standard engine is a 5.7L V8, producing 210 horsepower and 300 lb-ft of torque. Other engine options include a 7.4L V8 and a 6.2L diesel V8. The G3500 is available with a 4-speed automatic transmission or a 5-speed manual transmission.

Owners generally praise the G3500 for its powerful engines, rugged construction, and spacious cabin. However, it has received criticism for its poor fuel economy and dated interior.

Engine

5.7L V8

• Throttle Position Sensor Failure
  • Description/Symptoms: Erratic engine behavior, lack of response to throttle input.
  • Solution: Replace the throttle position sensor.
  • Estimated Cost to Fix: $100-$200+
  • Recalls: None Found
• Intake Manifold Gasket Leak
  • Description/Symptoms: Loss of coolant, rough idling, poor engine performance.
  • Solution: Replace the intake manifold gaskets.
  • Estimated Cost to Fix: $300-$500+
  • Recalls: None Found

7.4L V8

• No Issues Found

6.2L Diesel V8

• Fuel Injector Failure
  • Description/Symptoms: Hard starting, poor engine performance, black smoke from exhaust.
  • Solution: Replace the faulty fuel injector(s).
  • Estimated Cost to Fix: $500-$1000+
  • Recalls: None Found
• Turbocharger Failure
  • Description/Symptoms: Loss of power, excessive smoke from exhaust, whining or whistling noises.
  • Solution: Replace or rebuild the turbocharger.
  • Estimated Cost to Fix: $1200-$2500+
  • Recalls: None Found

Transmission

4-Speed Automatic

• Leaking Transmission Pan Gasket
  • Description/Symptoms: Transmission fluid leak beneath the vehicle.
  • Solution: Replace the transmission pan gasket.
  • Estimated Cost to Fix: $100-$200+
  • Recalls: None Found

5-Speed Manual

• Synchronizer Wear
  • Description/Symptoms: Difficulty shifting gears, especially when downshifting.
  • Solution: Replace the worn synchronizers.
  • Estimated Cost to Fix: $500-$1000+
  • Recalls: None Found

Suspension

• Front Shock Absorber Failure
  • Description/Symptoms: Poor ride quality, excessive bouncing, uneven tire wear.
  • Solution: Replace the worn shock absorbers.
  • Estimated Cost to Fix: $200-$400+
  • Recalls: None Found
• Leaf Spring Breakage
  • Description/Symptoms: Sagging rear end, uneven tire wear, loss of stability.
  • Solution: Replace the broken leaf spring(s).
  • Estimated Cost to Fix: $300-$600+
  • Recalls: None Found

Electrical

• Alternator Failure
  • Description/Symptoms: Dimming lights, slow cranking, electrical system malfunctions.
  • Solution: Replace the alternator.
  • Estimated Cost to Fix: $300-$500+
  • Recalls: None Found
• Battery Drain
  • Description/Symptoms: Battery goes dead overnight, even with a new battery.
  • Solution: Identify and fix the source of the drain, such as a faulty light switch or module.
  • Estimated Cost to Fix: $100-$300+
  • Recalls: None Found

Exterior

• Rust on Frame and Body
  • Description/Symptoms: Corrosion on metal surfaces, especially in areas like the frame and fenders.
  • Solution: Sand and repaint affected areas, apply rustproofing.
  • Estimated Cost to Fix: $500-$2000+
  • Recalls: None Found
• Headlight Switch Failure
  • Description/Symptoms: Headlights won’t turn on or switch between different modes.
  • Solution: Replace the headlight switch.
  • Estimated Cost to Fix: $100-$200+
  • Recalls: None Found

Interior

• Dashboard Cracking
  • Description/Symptoms: Cracks on the dashboard, especially around the glove box and air vents.
  • Solution: Replace the dashboard.
  • Estimated Cost to Fix: $500-$1000+
  • Recalls: None Found
• Seat Belt Retractor Failure
  • Description/Symptoms: Seat belts don’t retract or lock properly.
  • Solution: Replace the seat belt retractor(s).
  • Estimated Cost to Fix: $100-$200+ per retractor
  • Recalls: None Found

Summary

The 1991 GMC G3500 is a reliable and capable heavy-duty truck, but like any vehicle, it has its issues. Some of the more common problems include throttle position sensor failure, intake manifold gasket leaks, leaking transmission pan gaskets, and front shock absorber failure. While these issues can be costly to fix, they are relatively straightforward and can be addressed by a qualified mechanic. Overall, the G3500 remains a popular choice for those who need a powerful and durable workhorse.