08 Sierra 2500hd - Arm Strong Steering?

[yamaho]

I have a 08 Sierra 2500HD/6.0L/Allison I bought for towing has approx 90,000 miles on it. Recently I noticed an occasional loss of power steering at idle.....it makes it very difficult to steer unless I rev up engine. Has happened twice now while towing, it seems to effect the brakes as well.....I assume the share a pump? Fluid seems fine? Should I flush, or is something showing signs of failing and should be replaced?

[sonjaab]

Sounds like the steering EVO sensor !

 

Mine was replaced on my truck. Same as yours.

There are other posts and a TSB here somewhere.

[Shaners]

The power steering pump is also the boost for the power brakes. If you are running oversized tires GM will say that is the reason for your problems,

[sonjaab]

Check on a TSB for high steering effort.

This one is for 04-06 and possibly other years:

05-02-32-008B 07/18/2007 Steering - Lack of Assist at Low Speeds

 

Also:

TSB #070232001 -- REDUCED STEERING EFFORT (DIAGNOSE/REPLACE STEERING WHEEL POSITION SENSOR). *KB (NHTSA ID #10021450, MARCH 01 2007)

[sonjaab]

This bulletin isn't for the '08 model-year but might be your problem for your truck..........

 

 

 

Document ID# 1848789

 

 

 

 

Subject: EI06002 - 670 Gear Box Power Steering Pump, P/S Performance Concerns #05-02-32-008A - (07/20/2006)

 

Models: 2003-2006 Cadillac Escalade, Escalade ESV, Escalade EXT

2003-2006 Chevrolet Avalanche, Silverado, Suburban, Tahoe

2003-2006 GMC Sierra, Yukon, Yukon Denali, Yukon XL

 

This bulletin is being revised to close the engineering investigation and provide repair information. Please discard Corporate Bulletin Number 05-02-32-008 (Section 02 -- Steering).

 

Condition

Some customers may comment on a lack of steering assist when stopped or during parking lot type maneuvers. A lack of steering assist could occur if the brakes are applied and turning the steering wheel with the vehicle stopped or during parking lot type maneuvers. This condition will go away or greatly improve once vehicle begins to move or is above parking lot speeds. This concern can be aggravated by worn tires, low tire air pressure, low power steering pump pressures, and tires larger than stock size.

 

Correction

Important: In all cases, it is recommended that the proper tire size and the maximum tire pressure is set according to the manufacturer’s specification as noted on the door placard; especially for the front tires.

 

Perform the "Power Steering System Test" found in SI. Make any necessary repairs based on system diagnosis.

1.1. FOR 2500 AND 3500 VEHICLES ONLY - If diagnostics did not lead to any repair, this concern is a normal operating characteristic. No further repairs should be made. A Field Product Report should be submitted - refer to Corporate Bulletin Number 02-00-89-002D.

 

1.2. FOR 1500 SERIES VEHICLES ONLY - If diagnostics did not lead to any repair, this concern is a normal operating characteristic.

 

If the vehicle is equipped with a 670 gear box, replacing it with a 680 gear box may increase the customer satisfaction.

To determine if the vehicle is equipped with a 670 gear box, inspect the mounting bolts that attach the stub shaft housing. A 670 gear box will only have 3 mounting bolts. If the stub shaft housing does not have any mounting bolts or has 4 bolts - DO NOT PROCEED WITH THIS BULLETIN. The vehicle is not equipped with a 670 gear box.

If replacing a 670 gear box with a 680 gear box, it will be necessary to replace the power steering gear, union fitting and both inlet o-ring seals.

Parts Information

Part Number

Description

 

88965542

Power Steering Gear

 

26025709

Union Fitting

 

26001594

Inlet O-ring Seal

 

 

Warranty Information

For vehicles repaired under warranty, choose the one labor operation that reflects the corrective action:

 

Labor Operation

Description

Labor Time

 

E9050

Pump Assembly, Power Steering - Replace

Use Published Labor Time

 

E9740

Gear Assembly, Power Steering - Replace

Use Published Labor

[yamaho]

Awesome info guys! I tried driving the truck last night, and the brakes fade and steering goes to none now at idle or low speed driving. I will have to take to dealer, off warranty (too many miles).......was hoping to repair myself.

 

Dealer can't get in for a week...he mentioned it's possibly the hydroboost. Which should I replace first, the pump or the hydroboost? Works with engine rev'd but not at idle? Would this be the pump? Anyone with some thoughts/experience with this?

[sonjaab]

Possibly covered under the 5/100 powertrain ?

 

When my EVO went it had no steering assist even in neutral

with higher RPMs. First dealer claimed it was from my snowplow being mounted and blew me off!

Mine was still under the 3/36.

The truck is VYU plow prep equipped so I wanted no BS excuses ! I hammed them on the service satifaction survey from GM and took it to the second dealer! They fixed it no problem!

 

Take those TSB codes to your dealer................

[sonjaab]

IMO its best to pay the dealer that 1 hour diagnosis time to

find out what the issue is! No sense throwing $pendy parts

at it then finding out it was a $100 EVO sensor instead of a

$$$ hydro-boost pump or $$$ steering pump/box !

 

IT may be yer lucky day and its under warranty!