Hi - First time here. I spend a lot of time in the BMW forums trying to keep my car running, but have never had issues with our '06 Dodge Caravan (75,000 mi) so never had a need to visit here!

Anyway, I am getting loud whine after I've been on the highway for a long period of time at highway speeds. It gets louder when you step on the gas.

I saw a thread that was almost identical - whine after a long highway run - but it wasn't a throttle responsive whine, and people suggested the power steering issues.

This whine definitely responds to the throttle: low whine at idle, high loud whine on acceleration.

Thoughts?

 

It could still be the power steering pump. The filter in the bottom of the reservoir is most likely clogged and as the engine RPM goes up the whine will get louder. The pump is cavatating for the lack of fluid.

AT 75k miles I think this is your problem and you need to change the reservoir. I had the same problem after 60k miles. Not an expensive part at a parts store. Fluid is ATF+4.

 

Welcome to DF
I also agree with papaduck. The problem maybe the P/S reservoir. But don't rule out the pump as well.

 

I am willing to bet its the P/S reservoir strainer/filter screen that is clogged and therefor starving your pump of fluid. I have...had, the EXACT same issue. Tonight I actually replaced the reservoir on my '07 SXT with 80k miles on the clock. Guess what...no more whine!

Before you do anything jump on YouTube and search "dodge caravan noisy steering DIY fix." The guy that made the video does a decent job of explaining what to do step by step.

A couple of tips...
1. use a plastic liter bottle to catch the fluid on the return line side, works better than a gallon milk jug.
2. once you get the new reservoir installed (inlet line on, return line off in bottle, plug or tape off return male side since it will leak new fluid during this process) flush the system with a quart of ATF+4 fluid (I bought 2 qts of Valvoline ATF+4). It will help get most of the old particles out of the lines. Fill up the reservoir, start the engine, let it run for about 10 seconds, fluid should be barely coming out at that point. Repeat to your liking.
3. take your time with a flat head screwdriver when prying off the inlet (main) line on the back. It will be on there pretty snug, just work it around slowly.
4. use rags to keep spills to a minimum.

Good luck, proceed at your own risk...

 

Thanks a lot everyone for your great responses. I appreciate the tips for the DIY, but I think I'll leave this one to a professional.