Owners report multiple distinct steering failures across 2006 Sierras, often sudden and dangerous. Power steering pump failures appear at both low mileage (650 miles) and high mileage (150,000+), leaving the steering wheel immobile and, on diesel models with hydroboost, also killing the brakes—one owner lost both systems backing down a driveway. Several owners describe the steering wheel locking in place, either during braking or while driving, requiring hard force to unlock; one truck crashed into a bridge guardrail when steering seized at 30 mph. Rack and pinion assemblies go bad, and front tie rods fracture without warning during low-speed maneuvers. Loose or clunking steering columns create play and noise, especially at highway speeds in wind, with owners reporting the problem persists even after dealer parts replacement and lubrication. Front wheel bearing hub assemblies fail on both sides, causing severe wheel shake and loss of drivability; a GM-certified mechanic noted this is a known-failure pattern on GMC and Chevy trucks. Power steering fluid leaking into the brake system has recurred three times on the same vehicle. One owner reported the hydroboost as undersized for towing, creating excessive noise from day two of ownership. Dealers frequently cannot diagnose intermittent power steering loss and sometimes claim steering problems are normal design. No clear recall pattern emerges across these complaints.
Failure modes owners describe
Power steering pump failure
Power steering pump loses function suddenly, eliminating power assistance to the steering wheel. In at least one case, pump failure also disabled hydroboost braking because the system shares hydraulic pressure.
When: 650 miles, 154,000 miles; one case with no mileage stated
Symptoms owners cite: steering wheel becomes impossible or extremely difficult to turn; complete loss of power steering assist; backup braking system (hydroboost) fails when pump fails
Repairs/costs cited: Dealership replacement of power steering pump; one owner reported pump replacement followed by power steering line split two weeks later
Recalls/TSBs owners mention: Recall 09014 mentioned for steering column communication issue; no manufacturer recall noted for pump failures
Steering wheel lock-up
Steering wheel locks in place, either when applying brakes or while driving. Owner must apply significant force to unlock. Occurs intermittently.
When: No mileage stated; reported as recurring problem over time
Symptoms owners cite: steering wheel locks and becomes immobile; requires hard jerking to unlock; happens at least twice to one owner; occurs during braking
Repairs/costs cited: Dealership unable to repair after three attempts; another dealer told owner this was normal vehicle design
Recalls/TSBs owners mention: Manufacturer advised owner to take vehicle to dealer; no recall or TSB identified
Rack and pinion failure
Rack and pinion assembly becomes faulty, making steering stiff and difficult to turn. Failure occurred at high mileage.
When: 160,000 miles
Symptoms owners cite: steering wheel becomes difficult to turn while driving at 25 mph
Repairs/costs cited: Independent mechanic diagnosed faulty rack and pinion requiring replacement; repair completed
Recalls/TSBs owners mention: Manufacturer not notified
Intermittent power steering loss during low-speed maneuvering
Power steering assist drops out when turning the steering wheel at idle or low speeds, particularly during parking. Assist returns when vehicle begins rolling.
When: 32,000 to 35,000 miles; problem lasted approximately one year
Symptoms owners cite: power steering assist lost during low-speed turning and parking; power steering assist returns once vehicle rolls; brake pedal also drops slightly when stopping
Repairs/costs cited: Dealership checked twice; unable to address issue without hard codes or confirmed failures
Recalls/TSBs owners mention: No manufacturer response noted
Power steering fluid leak into brake system
Power steering hydraulic fluid leaks into the separate brake system, causing brake seizure. Recurring problem on same vehicle.
When: 161,108 miles; third occurrence on same vehicle
Symptoms owners cite: brakes seize; power steering fluid contaminates brake fluid
Repairs/costs cited: Hoses affected by brake fluid were replaced; repair completed multiple times on same vehicle
Recalls/TSBs owners mention: Manufacturer made aware of failure
Loose/clunking steering column or shaft
Steering column or hydraulic steering components develop play or looseness, producing clunking sounds and causing poor steering control. Looseness does not improve with lubrication.
When: No specific mileage; one case reported as ongoing issue
Symptoms owners cite: clunking or bumping noise from steering column; noticeable looseness in steering feel; vehicle wanders at highway speeds; symptoms worsen in high winds; poor driving and maneuver ability
Repairs/costs cited: Owner greased and lubricated entire steering mechanism without improvement; dealership replaced unspecified steering part in June 2009 without resolving issue
Recalls/TSBs owners mention: No manufacturer response noted
Front tie rod fracture
Front tie rod cracks and fractures, causing sudden steering loss. Failure occurred without warning during low-speed backup.
When: No mileage stated
Symptoms owners cite: left front wheel collapsed to pavement; steering lost during low-speed backup
Repairs/costs cited: Dealership replaced fractured front tie rod
Recalls/TSBs owners mention: No manufacturer response noted
Front wheel bearing hub assembly failure
Front wheel bearing hub assemblies fail on both driver and passenger sides, causing wheel shake and loss of driving ability. GM-certified mechanic reported high frequency of these failures on GMC and Chevy trucks.
When: No specific mileage; one case at 36,000 miles
Symptoms owners cite: wheels shake severely; vehicle becomes impossible to operate; grinding noise; brake smoke and diminished braking
Repairs/costs cited: Hub assembly replaced with new parts by GM-certified mechanic; mechanic noted GMC and Chevy trucks have repeated failures of this component
Recalls/TSBs owners mention: No recall or TSB noted
Power steering failure at highway speed
Power steering system fails suddenly while driving at highway speed, with burning power steering fluid odor preceding failure. Steering wheel turns but wheels do not respond.
When: 154,000 miles (different vehicle); one case at unknown mileage
Symptoms owners cite: burning smell from power steering fluid before failure; steering wheel becomes disconnected from wheels; complete power steering failure during curve at 50 mph
Repairs/costs cited: Vehicle crashed into guardrail; vehicle was totaled and towed to wrecking yard
Recalls/TSBs owners mention: No manufacturer contact; recall for pitman arm mentioned by another owner as related to total steering loss
Hydroboost undersizing for truck weight/towing
Hydroboost brake system is inadequately sized for the truck, producing noise and creating difficulty during towing operations uphill and downhill. Problem present from early ownership.
When: Two months of ownership (new truck)
Symptoms owners cite: excessive noise when using brakes; excessive noise when using power steering; difficulty with towing operations uphill and downhill; noise present from second month of ownership
Repairs/costs cited: Dealer determined no problems; issue unresolved
Recalls/TSBs owners mention: No manufacturer action taken
Brake and ABS light with front brake smoke
ABS and brake warning lights illuminate immediately after purchase, with front brakes producing smoke during initial drive. Problem unresolved despite multiple repair attempts.
When: 4 minutes after purchase; continues at time of complaint
Symptoms owners cite: ABS light on dashboard; brake light on dashboard; front brakes smoking; brake problems persist through multiple repair attempts
Repairs/costs cited: Owner attempted repairs numerous times without success; dealership offered no solution
Recalls/TSBs owners mention: No manufacturer response; dealership refused warranty remedy or vehicle exchange
Synthesized from 24 NHTSA owner complaints — unverified consumer
allegations, summarized for patterns. The verbatim filings appear below.