Is my power steering pump failing?

Jeff d

Apr 12, 2021
2000 TJ, 4.0, manual transmission, 83,000 miles

When my engine revs are falling and I’m coasting up to a turn the steering becomes heavy for a fraction of a second and then returns to the normal/expected amount of assistance. If I flip to neutral then keep my foot on the throttle to hold the revs up a little bit it doesn’t do this. If the engine’s been idling for a moment then it doesn’t do this either. It’s only when the revs are falling to idle when I attempt to steer.

This is my third 2.5” lifted TJ on 33s and it’s the first that’s behaved this way. It’s a recent development on this 2000 that I’ve had for about 10,000 miles. I don’t think it’s camber/caster related because it’s pretty consistent with the above conditions regardless of speed of travel or road conditions.

Does this sound like a leaky pump piston seal issue or could it be somehow steering box related?