if i am not mistaking they had told me the stabalizer bars (sway bars) when they are diffective. i am going to change does on my 96 dgc for that reason my front end makes a rattle noise The end links and sway bar bushings are prone to failure on 1996 and later vans.
The grinding noise in the front of a 1990 Dodge Caravan could be a cv joint. If it is, it probably only grinds when you take a sharp turn. There is one located on each side.
check your stabilizer links as well as your sway bar bushings. the sway bar bushings might look ok but what happens is the hole gets egg shapped causes clunkinking noise s going over bumps. just had the same problem in my shop. 2002 dodge caravan.
Starte could need a shim.
A dodge caravan may be experiencing rear brake noise due to needing new brake pads. This may also be due to worn rotors.
rack and pinion
There is a possibility that some bushels or mountings need replacing.
The noise can be comming from the weather stripping around the door, the wind passing past the antenna or from the wind around the luggage rack on acceleration.
drive belts tensioner/under chassis
Transmission mount
Bearing going bad?
The pump will need replaced if it is grinding.
Could be one of a number of things, as it could be in any vehicle.