This is going to be a tough one, both for diagnosis and repair!
The lower radiator hose connects to a steel pipe that runs under the intake plenum to the back of the water pump housing. Coolant leaking from that pipe will run either way, depending on which side of the van is lower. Those pipes don't corrode through very often so your chances of getting a bad one from a salvage yard are pretty small. They're the same on all the 3.0L engines on Chrysler cars and minivans. Only one bolt has to be removed from the transmission bell housing, then that pipe can be pulled out. There's an o-ring on the other end to seal it in the water pump housing.
The next step is to flush all of that stop leak crap out of there. Install new antifreeze. Failure to replace the antifreeze every two years is the biggest cause of corroded parts. The antifreeze will always be antifreeze, but it's the additives, namely the water pump lubricant and corrosion inhibitors, that wear out. Acids form in there too which is also why the coolant must be replaced regularly.
Once you're done flushing the system, there's going to be water in the block that won't drain out. I find it easiest to start by filling one full gallon of straight antifreeze, not that 50 / 50 mix stuff where they're selling you a half gallon of water. Next, add a half gallon of water, then a half gallon of antifreeze, until the radiator is full. Drive it through a few warm-up / cool-down cycles to mix it thoroughly, then check the freeze point. If it isn't good for minus 35 degrees, you can add antifreeze or water as necessary to the reservoir.
Thursday, October 9th, 2014 AT 5:16 PM