A V-5 is inherently unbalanced, as were the engineers who designed it! ;)
That's what I figured. Having been around engines and vehicles most of my life, engines with an odd number of cylinders are not balanced as well as the V-6 or V-8 or even inline engines.
I have a neighbor who works for a Dodge dealer and he said the same about Dodge's two biggest mistakes.
#1. Rushing to be the first with a V-10
#2. The PT Cruiser
This was also an objection to the first 90 degree V6 engines back in the early 60s. As it turned out, IIRC, the movement generated in any one direction by the unbalanced condition was so small and so brief at operating rpms that the vibrating parts 'floated' inside the crankshaft bearing clearances without ever transferring the vibration to the rest of the engine. Or so I heard.