brake booster

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Jan 24, 2009 | 08:00 AM

#31

vettdvr

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Joined: Jul 2006

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Quote:

Originally Posted by NAMDROF

99 F350 LB SW 4whl CC Auto 118K

OK so I have been hearing a slight groaning noise. Starting to get louder. Thinking it was the possibly the tach? I took my cheapo stethoscope and couldnt isolate it. I also went out to the booster but couldnt hear anything there nor Power steering pump. But today when I was re-starting after coming out of the Post Office when I applied pressure to the brake foot pedal it made a gurgle-ing type groan and settled in about a 1/4 inch lower??? So I am thinking booster? Whatya think?

Pump wear with increased fluid flow demand as you increase the load on it by depressing the pedal which is resulting in noise, would be my thought on the problem.

Check the pulley on the pump for side to side movement. There is suppose to be a little normal front to rear movement.

The vanes in the pump have worn down. I would change the fluid to see if that improves the noise. The new fluid will have less contaminates and changing will remove some of the "stuff" in the system.

Jan 24, 2009 | 05:14 PM

#32

NAMDROF

Mountain Pass

Joined: Jul 2005

Posts: 165

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Groaning noise

Thanks for the reply. The groaning noise is what I call it now, is the same pedal depressed or not. It doesn't change if I step on brake pedal or turn the steering wheel, it is constant. I got the Gurgling sound only once when I was stepping on the brake pedal when I put it in gear to back up. The pedal seemed to drop a 1/4 inch also.

So you think it's a fluid change in the pump? Use mercV?
Got nuttin too loose! Cheaper than a pump or new booster.

Thanks

Jan 24, 2009 | 06:45 PM

#33

vettdvr

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Quote:

Originally Posted by NAMDROF

So you think it's a fluid change in the pump? Use mercV?
Got nuttin too loose! Cheaper than a pump or new booster.

Thanks

I think the fluid change might help and it might solve the problem.

I would use the Mercon V given it was suppose to have Mercon III and it is discontinued.

When I changed mine I pulled the return line from the booster that went to the pump and routed it to a container (messy). Then with engine running I poured fresh fluid into the pump while the wife pumped the brake and turned the wheel left and right about 2". This caused the fluid to circulate out into the container. As the level went down I topped with fresh fluid. The old fluid came out black. After 3 qts it began to look better. This cleared up the groaning in my pump which sounds like very much like you have. If this doesn't work, they you might be in for a new (not rebuilt) pump.

Mar 21, 2009 | 12:00 PM

#34

samike71

New User

Joined: Mar 2009

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brakes and steering

I have read all replies and am not certain if there has been an actual diagnosis of the problem I am experiencing. I own a 2002 7.3 Powerstroke diesel. I was driving and felt my steering to be a bit scratchy???? I checked the steering fluid and it seemed to be ok. I went ahead and drove again but this time, I noticed that when making a turn that involved a tight 90 degree turn it would stiffen considerably, feeling like I lost the Power in the steering. On the same drive, I also felt my brakes give out, meaning they felt like they were not going to do their job of stopping me! I called the dealership and got the typical bring it in response, understandably so. They did suggest that the hydraulic power booster could be a problem. If anyone has suggestions please advise. Thank you in advance!

Mar 21, 2009 | 06:06 PM

#35

vettdvr

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Joined: Jul 2006

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Quote:

Originally Posted by samike71

This clearly sounds like loss of hydraulic pressure. This can come from at least 2 sources.

1) Failure of the power steering pump
2) Failure of the hydraulic pressure overpressure relief valve in the power steering pump.

Both would require change of the pump

. Hope this helps.