Def replace but The other thing you should replace to improve mpg considerably (if it hasn’t been done already) is your oxygen sensors. Those things tell the computer exactly how much fuel to put in the system based on air mix in your exhaust fumes. They should be replaced every 100k miles or so. As they get old they don’t read as well, and tend to dump more fuel into the system. My truck jumped about 3mpg or an additional 70 miles per fill up with new oxygen sensors.
I’d replace plugs every 30-50k miles. The electrode looks somewhat burnt away, and like it’s burning hot all together. I’d got with the closest to oem as you can get, and don’t cheap out.
This is an 08 chevy 2500 runs great, was my fathers, but were at 180k and and I know she could be running smoother
Def replace but The other thing you should replace to improve mpg considerably (if it hasn’t been done already) is your oxygen sensors. Those things tell the computer exactly how much fuel to put in the system based on air mix in your exhaust fumes. They should be replaced every 100k miles or so. As they get old they don’t read as well, and tend to dump more fuel into the system. My truck jumped about 3mpg or an additional 70 miles per fill up with new oxygen sensors.
I’d replace plugs every 30-50k miles. The electrode looks somewhat burnt away, and like it’s burning hot all together. I’d got with the closest to oem as you can get, and don’t cheap out.