1987 Plymouth Voyager Shutters and Shakes then stalls when

We have a 97 Grand Voyager. It has had the motor replced a few years ago (about 4). Had the transmission replaced about 2 years ago. Both while on trips - fun. We keep pretty care of it. And it has been a good car both before and after the repairs.

Recently we when we start it in the morning and put it in reverse it shutters and lurches and occasionally dies. It just started doing it in drive as well. But if we turn the motor off and restart it - usually a couple times it stops doing it seems to operate with out any further issue for the rest of that day. But the next morning it does the same thing again. Any advice? Engine or Transmission issue? What shop do I take it to.

Thanks.