Loud engine knock

low oil, dirty oil, wrong oil as far as repair If it still runs and doesn't leak oil you can pull pan and replace bearing rod etc assuming van is worth it. if it did throw the rod it usually goes through the block or pan and you'll need to replace or rebuild. I'd try to find an engine from a local yard or buy a short block wouldn't use dealer as it'll be costly. That's only if you love the Van and the rest is in good to better shape cause your getting c lose to tranny time as well as fuel pump replacement, AC work etc. As far as cost I'm no help best try the repair estamite section of this website. It's posible tyto get a lot of miles out of DC's &T&C's I have 225000 miles on a '96 Dodge caravan sport