Ok I need someone to verify my train of thought. 09 jku Rubicon on 35s. Noticed when I first bought it that power steering wouldn't help much on flat parking lot unless rolling. If the Jeep was nose down in a parking lot it was dead. Replaced power steering pump with a rebuilt. Now it's fine on flat, but nose down it's still a problem. I think since it was better after replacement it is the pump, I just f'ed up going rebuilt and should have used new.
It is a easy job so if community agrees that it's the problem I'll set into switching under parts warranty until I get a better one. Doesn't have any steering binding with more weight on the front, just lack of power steering and rpms doesn't help.

 

Most of those pumps are rebuilt. Are you sure you've got the air out of the lines? What's your tire pressure look like? I can't say I've noticed a dead pump on nose down, maybe I'll have to try tomorrow.

 

I can't say I see the thought process of how nose down would make any difference at all with a pump. Definitely not saying you're wrong, I'm just wondering the logic behind why nose down would prohibit the pump from working vs. flat land? Curious if I'm thinking about it wrong.

 

Only thing I can think of is that with the front end tilted down there's enough weight on the front tires that the friction between rubber and asphalt can't be overcome with the pressure. It doesn't have to be a steep decline either. Tires are around 32psi. Reason I think it's the pump is after I replaced it it was better than before, but there's still the nose down problem. And it really doesn't have to be steep at all. If front end is six inches lower down hill there's no power steering assist. Has been this way for 6 months now. When I replaced it I filled pump, attached hoses, filled, lifted front and cycled lock to lock engine off at least ten times. Topped off and cycles with engine on and checked fluid level. Have been to the mountains plenty with up and down, fluid hasn't dropped any.

 

Ah, I see what you're saying now. Makes sense when I think about driving on the pavement with tires that are aired way down and how hard it is to turn them at a dead stop. I've been bit by remanufactured parts a few times, most recently a starter. I've gotten to where I try to buy new if at all possible.

 

This. When I changed mine, the install procedure required a vacuum pump and a special adapter plate to pull a vacuum on the power steering pump I used a rubber stopper whittled down to fit in place of the PS pump cap with a hole drilled in it (actually more difficult than that sounds, LOL). Stuck a piece of tubing through that hole and used a hand vacuum pump similar to this ...

https://www.summitracing.com/parts/l...QaAm1oEALw_wcB

I know some folks say you can do the job without following that procedure, but if that's what you did, suggest pulling a vacuum to see if that corrects your problem.

 

Is the steering any better if you raise the rpm ? Sitting still nose down in neutral, does the steering effort change when you give it a little gas? Higher rpm more fluid flow from the pump,

 

Funny. After my new engine change I just did it the old way - filled it, ran engine, back and forth on steering wheel, check level, filled it, repeat a couple of times. No issues even out wheeling. Did you use ATF 4 fluid?
I believe the pulley is a taper fit so is it slipping? Technically it could do that and the belt would hold it on the pump.

 

Correct fluid, while thinking of a response it dawned on me to try airing up the tires more just to see if it's better. If it is then I think it is just a pump pressure issue. The 35 milestar mt are pretty grippy at lower air pressures. I'll check back in when I get a chance to test it out.

 

What air pressure are you running?