• Thinkstock Images/Comstock/Getty Images
  
  The 2003 Chevy 4.3 L, V-6 engine is designed and manufactured by General Motors for use in its GMC and Chevrolet lines of vehicles. The 2003 vehicles outfitted with the 4.3 L include all models of the Astro minvan and Blazer SUV and certain Express van and Silverado truck models. Engine and torque specifications vary across the four models.
  
  

Astro and Blazer

• The 2003 Astro and Blazer are outfitted with the same 4.3 L engine, with 190-horsepower at 4,400 rpm and 250 foot-pounds of torque at 2,800 rpm. Payload and maximum towing capacity are 1,579 lbs. and 5,400 lbs., respectively.
  
  

Express

• Like the Astro and Blazer, several Express van models--the Base Rear-Wheel Drive G1500 Cargo, Upfitter Rear-Wheel Drive G1500 Cargo, Base Rear-Wheel Drive G2500 Extended Cargo and Base Rear-Wheel Drive G2500 Cargo--are available with a 4.3 L engine, with 190 horsepower and 250 foot-pounds of torque. Unlike the Astro and Blazer, these Express models have a payload of 1,368 lbs. and a maximum towing capacity of 6,400 lbs. The Base Rear-Wheel Drive G1500 Passenger and LS Rear-Wheel Drive G1500 Passenger Express models are outfitted with a 4.3 L engine, with 200 horsepower at 4,400 rpm, but they are capable of the same 250 foot-pounds of torque. The payload and maximum towing capacity for the more powerful Express models is 1,955 and 6,400 pounds, respectively.
  
  

Silverado 1500

• The 2003 Silverado has an optional 4.3 L V-6, with 200 horsepower at 4,600 rpm and up to 260 foot-pounds of torque at 2,800 rpm. It is has a payload of 1,821 lbs. and a maximum towing capacity of 9,000 lbs.