Really bizarre power steering issue

PETERK821

MEMBER
TOYOTA 4RUNNER

2004 4-Runner LTD 4WD V8, 39,000 miles. REALLY odd power steering issue that has me completely stumped. Power steering seems to "fade" at times. It will have perfectly responsive power steering and light steering effort for a day or days at a time. Then, out of the blue it will stiffen up. It does NOT completely fail, but rather it feels as though about 20-30% more steering effort is required and will stay this way for a day or days at a time. The feel is more or less "rubbery" when its doing this. Has basically had these symptoms for months.

Replaced pump twice and rack and pinion unit twice. Same exact issue so I think I've ruled those out. Ball joints are in good shape.

I've tried to see if it has anything to do with temperature but it really seems to just be random. One day its great, next its "reduced power steering" as I am calling it. Then, its great again.

Does anyone have any ideas? I'm desperate at this point.

1 Reply

SERVICE WRITER

MECHANIC
9,123 POSTS

It may be a case of cavitation, that is air created in the system, a restriction in a line?

My truck was doing what you describe, I had added a bottle of lucas power steering conditioner to it and it went away. I don't normally subscribe to snake oil, but this worked. Some fords had a problem like this, that required a special procedure to remove air from the system, but haven't seen it on these.