The Daimler-Chrysler 4.7 Engine was their first truly fresh new V-8 engine for over forty years. This new engine had better power, gas mileage, and emissions than the 5.2 liter engine that it replaced. A new truck V6, the 3.7, was established on it, superseding the 3.9 liter V6 founded on the 5.2. The engine was reportedly intended as a substitute for the revered 4-liter AMC I-6, with the 3.7 to replace the AMC 2.5. EGR and knock sensors were adjoined in 2005.
In 2007, Chrysler substituted the 4.7 liter V8 with a new version. Power went from 230 hp to 290 hp (and up to 320 lb-feet of torque), and with that change, gas mileage climbed, and noise and vibration decreased. The new 4.7-liter V-8 features 5.7-Hemi emphasizes such as two spark plugs per cylinder, with a high 9.8:1 compression ratio, and more positive port flow; but it has a new slant/squish combustion system plan.