Steering Gear Box Failing?

[whitefish]

I have a 2005 Silverado 4x4 Z71 with a 4.8. I tried doing a search on steering gear box failures on GM-trucks and Google. Not many examples came up on google, nothing on GM-Trucks.

 

I've noticed thats its getting harder and harder to turn the front wheels, especially when at a stand still or moving slowly. At first I though it was the power steering pump, but the pump wasn't making any the typical whining noise symptomatic of a failing pump. But, I replaced the pump anyways, No difference, except the Cardone reman I have makes a nice whine when I turn at any speed (loader at low speed). Should have left the old pump in.

 

As a note, I flushed and bled that power steering system using methods shown on Cardone's website. I used Prestone P/S fluid. The fluid flowed freely when I had the return line off and flushing the system, so the pump worked fine. BTW - instead of cranking the engine to run the P/S pump, I rigged up a system that ran a belf off of my cordless drill so that there was no danger of running the pump dry.

 

So, all I can think of is my gear box is on its way out. Is this possible? Do the symptoms sound rights?

 

Thanks!

[Beer Belly]

I believe there was a Service Bulliten out on difficulty steering ???

[gmtech4]

Recirculating Ball System






(1)
Power Steering Return Hose

(2)
Power Steering Pressure Hose

Test Description

The numbers below refer to the step numbers on the diagnostic table.

The pump for internal leaks

Important: Power steering hoses may not look kinked, but have a layer
separation causing the inner hose to collapse and restrict power steering fluid
flow.

The power steering pipes and hoses for kinks

1. • This step tests the system for restrictions.
   
   
   • This step tests the following components for the following
     conditions:
   • 
     
   
   
   • This step tests the ability of the pump to regulate flow at maximum
     pressure.
   
   
   • This step tests the ability of the pump to regulate flow under
     normal operating conditions.
   
   
   • This step tests the internal components of the pump and the gear.

Power Steering System Test

Step

Action

Value(s)

Yes

No

DEFINITION: The Power Steering System Test Procedure will perform the
following functions:

• Test the operation of the hydraulic power steering system.
• 
  
• Test the operation of the power steering pump and power steering gear.
• 
  
• Identify restrictions in the system.

1

Inspect the power steering fluid for the following indications of
contamination:

• Milky fluid - water
• 
  
• Brown fluid - burnt
• 
  
• Debris in fluid - plastic or dirt

Is the fluid free of contamination?

—

Go to Step 3

Go to Step 2

2

Flush the power steering system. Refer to Power Steering
System Flushing.

Did you complete the procedure?

—

Go to Step 3

—

3

Important: In order to accurately diagnose the system, the malfunction
must be present during the test procedure.

Attempt to duplicate the condition.

Is the condition present?

—

Go to Step 4

System OK

4

2. Turn the ignition switch to the OFF position.
3. 
   
4. Place a drain pan under the vehicle in order to catch any
   power steering fluid.
5. 
   
6. Disconnect the power steering pressure pipe/hose from the
   power steering pump or the power steering gear as necessary.
7. 
   
8. Install the J
   44721 Power Steering System Analyzer .
9. 
   
10. Fill the power steering system. Refer to Checking and
    Adding Power Steering Fluid.

Did you complete the installation?

—

Go to Step 5

—

5

Notice: Refer to Steering Wheel in the Full Turn
Position Notice.

2. Fully open the J 44721 valve.
3. 
   
4. Start the engine.
5. 
   
6. Turn the steering wheel and BRIEFLY hold the steering wheel
   against the steering stop in order to release any trapped air from the system.
7. 
   
8. Inspect and ensure that all of the power steering pipe/hose
   connections are not leaking.
9. 
   
10. Make sure the steering wheel is OFF the steering stop,
    observe the pressure reading.

Is the pressure reading greater than the specified value?

1525 kPa

(221 psi)

Go to Step 6

Go to Step 7

6

Important: A restriction may be present in the power steering system.
Turn OFF the engine IMMEDIATELY.

Locate and repair the restriction.

Did you complete the repair?

—

Go to Step 18

—

7

2. Allow the engine to run until the engine reaches full
   operating temperature.
3. 
   
4. Record the pressure reading and flow reading.
5. 
   
6. Partially close the J 44721 valve until the system pressure
   reaches the specified value, then record the FLOW reading.
7. 
   
8. Subtract second flow reading from the first flow reading.

Is the flow DECREASE greater than 3.8 L (1 gal) per minute?

4827 kPa

(700 psi)

Go to Step 13

Go to Step 8

8

Notice: Do not leave the valve fully closed for more than 5 seconds,
or the pump could be damaged internally.

Fully close then open the J
44721 valve 3 times. Record all of the high pressure readings. Refer to Power Steering
Pump Specifications for power steering system pressure relief
specifications.

Are the 3 high pressure readings within specifications?

—

Go to Step 9

Go to Step 15

9

Are the three high pressure readings within 245 kPa (50 psi) of each other?

—

Go to Step 10

Go to Step 14

10

2. Increase the engine speed to approximately 1,500 RPM.
3. 
   
4. Record the flow reading. Refer to Power Steering
   Pump Specifications for power steering system pressure specifications.

Is the actual flow reading within specifications?

—

Go to Step 11

Go to Step 13

11

Is the difference between the actual flow reading and the maximum flow
specification more than 3.8 L (1 gal) per minute?

—

Go to Step 16

Go to Step 12

12

Notice: Refer to Steering Wheel in the Full Turn
Position Notice.

Turn the steering wheel from steering stop to steering stop and record the
FLOW readings at each stop.

Is the flow LOWER than 3.8 L (1 gal) per minute?

—

Go to Step 18

Go to Step 17

13

Replace the power steering pump. Refer to Power Steering
Pump Replacement.

Did you complete the replacement?

—

Go to Step 18

—

14

2. Remove the power steering pump flow control valve. Refer to
   Power
   Steering Pump Flow Control Valve Replacement - Off Vehicle.
3. 
   
4. Inspect the flow control valve.
   

   If any burrs or scratches are noticed on the flow control valve, replace the
   flow control valve. Do NOT attempt to clean the flow control valve. Refer to Power Steering
   Pump Flow Control Valve Replacement - Off Vehicle.

5. 
   
6. Inspect the flow control valve bore.
   

   If any burrs or scratches are present in the control valve bore, replace the
   power steering pump. Refer to Power Steering
   Pump Replacement.

Did you complete the repair?

—

Go to Step 18

—

15

Replace the power steering pump flow control valve. Refer to Power Steering
Pump Flow Control Valve Replacement - Off Vehicle.

Did you complete the replacement?

—

Go to Step 18

—

16

2. Remove the power steering pump flow control valve and
   inspect for any wear or damage. Do NOT disassemble the flow control valve.
3. 
   
4. If the flow control valve is worn damaged, replace the flow
   control valve. Refer to Power Steering
   Pump Flow Control Valve Replacement - Off Vehicle.

Did you complete the repair?

—

Go to Step 18

—

17

The power steering gear is leaking across the piston or bypassing the valve
circuit. Replace the power steering gear. Refer to Steering Gear
Replacement.

Did you complete the replacement?

—

Go to Step 18

—

18

Test the power steering system for the original condition.

Does the original condition still exist?

—

Go to Step 5

Go to Step 19

19

2. Disconnect and remove the J 44721 from the vehicle.
3. 
   
4. Connect the vehicle power steering pipes/hoses.
5. 
   
6. Bleed the power steering system and add fluid as necessary.
   Refer to Power Steering
   System Bleeding.

Did you complete the repair?

[gmtech4]

Power Steering System Bleeding
Important:

◦Use clean, new power steering fluid type only. See the Maintenance and Lubrication subsection for fluid specifications. Refer to Fluid and Lubricant Recommendations.
◦Hoses touching the frame, body or engine may cause system noise. Verify that the hoses do not touch any other part of the vehicle.
◦Loose connections may not leak, but could allow air into the steering system. Verify that all hose connections are tight.
Important: Power steering fluid level must be maintained throughout bleed procedure.

 1. Fill pump reservoir with fluid to minimum system level, FULL COLD level, or middle of hash mark on cap stick fluid level indicator.
Important: With hydro-boost only, the oil level will appear falsely high if the hydro-boost accumulator is not fully charged. Do not apply the brake pedal with the engine OFF. This will discharge the hydro-boost accumulator.

 2. If equipped with hydro-boost, fully charge the hydro-boost accumulator using the following procedure:
2.1. Start the engine.
2.2. Firmly apply the brake pedal 10–15 times.
2.3. Turn the engine OFF.
 3. Raise the vehicle until the front wheels are off the ground. Refer to Lifting and Jacking the Vehicle.
 4. Key on engine OFF, turn the steering wheel from stop to stop 12 times.
Vehicles equipped with hydro-boost systems or longer length power steering hoses may require turns up to 15 to 20 stop to stops.

 5. Verify power steering fluid level per operating specification. Refer to Checking and Adding Power Steering Fluid.
 6. Start the engine. Rotate steering wheel from left to right. Check for sign of cavitation or fluid aeration (pump noise/whining).
 7. Verify the fluid level. Repeat the bleed procedure, if necessary.

[whitefish]

Thanks Rob - I'm probably not going to have access to a "J44721 Power Steering System Analyzer". Is there an alternative? Is this a TSB or a recall? In other words, would a service center look at this at no charge?

 

i don't believe I'm getting air into the system because I don't see bubbles or frothing in my P/S fluid (but you never know). Metal parts of my P/S lines were touching the frame and steering box, so I moved these to see if it helps.

 

I'm not positive, but I'm pretty sure I don't have hydro boast for the P/S system. I only see a pressure and return line attached to the steering gear box.

 

Beer Belly, do you happen to know the TSB number?

[gmtech4]

that is daignoses from the service manual ,there is no freebe for you ,,,,

 

i posted that to show the process to diagnose the p/S system, and how to bleed the system properly ,,,,,

 

dont go and guess what is wrong if anything ,,is my point

 

you replaced the pump for no reason already,try not to do that again,,,terrible habit,hard on wallet !!!!

 

good luck

[whitefish]

dont go and guess what is wrong if anything ,,is my point

 

you replaced the pump for no reason already,try not to do that again,,,terrible habit,hard on wallet !!!!

 

Perhaps, but $40.00 is cheaper than the alternative.

 

I'll try bleeding the system using the approach posted. Thanks again.

[Duelin]

The first thing I would do is undo the tie rod ends and rotate each wheel and see if there is anything binding in the suspension. Just a thought before you start changing out steering boxes.

[Beer Belly]

My '06 had intermittent (more often than not) hard steering turning left.....I believe it was here that someone replied with a service bulletin on replacing the steering the box depending on part number, or something of that sort