I am new to the forum and this is my first posting. I purchased a 1996 LT4 in 2006 with about 36000 miles. I’m at about 40000 now. Initially the car randomly made a pulsing sound when turning at slow speeds (e.g. into driveway) after reaching normal operating temperatures. There is no pulsing when cold starting. Lately, the pulsing has increased even with the slightest turn of the steering wheel, again at slow speeds. At straight highway speeds with little turn of the steering wheel, the sound does not occur, hot or cold.

The pulsing can be felt through the steering wheel, but not as a strong vibration.

There is no indication of a leak. The power steering fluid level appears ok.

In neutral and still, as engine speed increases, the steering wheel can be turned without pulsing. However, when slowed to idle rpm, the sound returns as soon as the steering wheel is turned in either direction (again car is not moving).

Based upon searches of this forum, possible solutions are (1) drain fluid completely and replace, (2) replace pump, (3) check PS cooler. I’m assuming it’s not the rack.

I’m eliminating front end alignment and brakes because sound could be heard when the car was not moving.

Tire tread and inflation are ok.

I would appreciate any guidance, especially if others have experienced the same symptoms. Any history with the PS cooler, e.g, fouling, plugging and effect on steering?

Thanks

 

my frist thought is rack. had mine changed last year but it was leaking something about seal getting old and fluid bypassing them. so i would check that frist. sorry i cant help more

 

You also want to check the water pump. See if any fluid is dripping from it. When it leaks, it drops fluid on the power steering pulley causing it to slip (and squeal). I just went through this myself...after I replace my rack (but at least I now have a sport rack)...just something else to check.

 

I can't say it is or isn't the rack. No fluid leaking from water pump. No belt/pulley squeal.

I raised the front end to check outside of cooler. It was clean. While up, I ran the engine up to 190+ degrees. I could turn the wheel to each extreme with no noise. I am not surprised since there was no load. I thought if the rack wasn't meshing properly, I might hear something. On the ground, the pulsing sound was load at the slightest turn.

Yesterday, I drove the car to nearby parking lot to heat up the engine. At about 130 degrees water temp the pulsing sound started.

I then changed the power steering fluid by fill and siphon method until noticeable change from very dark to almost clear (valvolene synthetic) occurred. No improvement - still very loud pulsing sound even at the slightest turn of wheel at idle and up to 3000 rpm.

I think I'll take it to local Chevy dealer, but am concerned that I might damage the power steering system.

Any comments??

 

Check your belt for a blob of grease. Mine did that after I "cleaned" things up. I thought I got the grime off of everything, but a little ball stuck to the back of a new belt and went around and around with it. Didn't notice anything till you put a little load on the steering, then...bump bump bump! Had to get another new belt and Idler pulley. That little ball of old road grease stuck to the belt and beat it till you could see cord showing and made my plastic idler pulley look like the surface of the moon!

 

Sounds like you PS pump is going out. Mine died gradually over about a year, with the sound getting gradually louder until it failed suddenly - no sound any more, no power steering.

The dealership will probably want to replace your PS pump, pulley, belt, fluid and rack and charge you for all of it.

 

thank you all

 

Had the car flatbedded to chevy dealer. Dealer diagnosed "binding vanes" in the power steering pump. Pump was replaced along with new belt (old one was cracked). No more noise. Steering back to normal.

No root cause was identified.

 

So how much did that trip to dealership cost you? My 96 Lt1 is making a whinning moaning noise but not every time. I check the fluid and it's full. Not sure where or what to do next.

 

The net towing cost was $25. My wife is AAA member so we paid on incremental miles over AAA free miles. The cost to replace the power steering pump and belt and fluid was about $400.

The noise that I heard gradually got louder, up to a point at which I would not drive the car because even the slightest turn of the steering wheel in either direction resulted in a very loud pulsing /chattering (hard to describe).

 

For those with similar trouble. I had this going on last fall, replaced the serpentine and all is good. However, I agree with the post that says check your water pump, been there done that too. But as the belt wears it gets hard slick and brittle. It seems that steering is the first to show the symptoms.

 

even in my case?