My 98 Grand Caravan 3.8L has been making a squealing/whining noise for a while now. When it first started, it would mostly do it during colder weather, and eventually would just abruptly stop after the van was ran a while.

Lately it's been doing it no matter the weather, and taking longer to stop. From reading around, it seems as though it might be the power steering.

To start trying to diagnose and fix it, I'd like to start with the basics. I read a lot about a common problem with the filter screen in the reservoir clogging up. However, most of the things I see about this refer to the reservoir being round and sitting on top of the engine. Mine has a squarish power steering reservoir on the passenger side of the engine compartment, and I can find next to no information about this style, let alone if it's similar to the round one and has the filter screen inside.

I also came across this part for sale: http://www.partstrain.com/store/deta...BoCcGMQAvD_BwE

But there are no details about this, so I'm not sure if this is the kind of filter this van would have instead of the filter in the reservoir, or if this is some sort of aftermarket thing.

If anyone has experience with and is familiar with this style of power steering reservoir on these Caravans, I'd appreciate hearing any details you could share!

 

So I took the reservoir off and emptied it. I can confirm that the squarish power steering reservoirs on these vans have no filter in the bottom.

I flushed the fluid, but I'm not quite convinced anymore that this squealing has anything to do with the power steering. The steering has always been fine, and never makes noise when turning the wheels. I would think that if it was a case of the rack-and-pinion being starved of fluid, I would also hear it more when turning the wheels, and this is not the case at all.

I'm not so sure it's even what would be the next most obvious thing, the belts. If I have the hood up and rev up the engine from the engine compartment, it sounds as though the noise comes from the back right area of the engine compartment. But perhaps it's just misleading. I never thought it would be the belts, however, since back when the noise first started, it would abruptly and completely stop after the van was ran a little while.

The noise definitely escalates in pitch with the RPMs of the engine, so I also wouldn't think it would be a dirty transmission filter either, and I really don't have any tranny issues with this thing.

Any ideas would be appreciated!