Robin,
Chrysler had two engines that were essentially V8's with two cylinders removed. The better one is the Jeep/Dodge 3.7L V6, which is the 4.7L engine minus two that originated in 2001 in the Jeep Liberty and replaced the 3.9L V6 that had been the mainstay in the mid-sized trucks from '87 to 2002. The 3.9L was derived from the 318 V8 and was pretty much a stone, developed because of the limited room under the early Dakota hood not allowing a V8 or in-line six. The later ones improved with sequentially fired multi-port injection, but the entire line was only marginally acceptable with a manual tranny where you tended to lug down the rpm's and have all kinds of vibrations. I think that the older 3.9's held together OK, but the performance was not the best.

Here's a link to the newer 3.7L information - Allpar presents the Dodge/Jeep 3.7 liter V-6
and here's one to the older LA engine series which had the 3.9L - The 3.9 liter LA-series Dodge V6 engine