Power steering/brake issue

[Bigbill756]

I don't know where else to post this, the topics and threads are so vast. We have a Class A 1993 Allegro Bay 33 ft. with slide gas coach, we bought and are third owners. 80,000 miles, everything is still in good shape except...it is having power steering issues and I was hoping for some insight. When the vehicle is in Park, the power steering appears normal and you can turn the wheels both directions. When it is put in Reverse or Drive, the power steering pump whines and the wheels are difficult to turn, and it also makes the brakes really mushy and it's sphincter tightning at stop lights and intersections. The brake fluid reservoir appears full when I check it. The hydraulic fluid is also full. I read in a thread to contact Tiffin directly, as they supposedly keep all records of their vehicles, but was told by them they sold off the P30 series chassis a long time ago and only deal in legacy parts, with no service people to talk to. I have read some related posts on this forum and others with no definitive answers and people talking about spending thousands at service centers wthout solving the problem. Anyone else experience symptoms like this? I need to know whete/what to look at. Thanks for any insight you might provide...

[TonyMac]

I find it very odd that the pump can turn the wheels when the rig is stationary, but not when it is moving, if that is what you are saying. Your power steering pump also supplies boost to your power brake system. When stationary with your foot on the brake and turning the wheels, you are asking the power steering pump to both supply pressure to the brake booster and turn the steering wheels. These pumps get weak with age, maybe replacing the pump could get it working correctly.

[Bigbill756]

Thanks for the reply TonyMac, and yes, that's what I'm saying. It's weird. I'll start with the pump and see if it mitigates the problem...
Thanks!

[John Lorang]

On my old Class A on a P30, the brake used the hydraulic pump for power brakes as well as power steering.
Mine had a two belt setup.
I am not sure but the auto parking brake setup my use the hydraulic pump also. It is a known problem with this auto parking brake setup to cause trouble.
You might search for parking brake problems on a P30.

[Bigbill756]

Thanks John! In all the threads in forums like this and other searches, this park brake relationship has been mentioned, but with no real details to solving it that I've seen. Just that there is a relationship. I'll start researching using your suggestion. Thanks again!