Power steering locking up intermittently
We recently replaced the power steering pump & the serpentine belt on a 2007 Lexus LX470. Now, when we try to make a hard turn, the steering will intermittently lock up. Any ideas? We replaced the fluid.

The Lexus LX series represented the Japanese luxury automaker's initial trek into the SUV market. First appearing in the mid-1990s as the LX 450, this midsize SUV was virtually indistinguishable from Toyota's Land Cruiser. While this similarity spoke to the LX's off-road ability, many were left with questions about its value in its class. In the past decade, the LX has seen little change, and 2007 is essentially a carry-over year. A Limited Edition LX 470 is new for this year, with production numbers commensurate with its name. The second generation, which began back in 1998, will end after 2007. An all new LX should appear for the 2008 model year. Aside from the special edition that is offered this year, the LX 470 is only offered in one trim. While the LX is a capable 4x4, its interior has been dressed to be reminiscent of the LS sedan. Standard features include a premium 11-speaker Mark Levinson audio system with an in-dash CD changer, leather/heated/power seats, automatic climate control, a DVD-based navigation system with a backup camera, a moon roof, auto-dimming mirrors, and most other things you could think of. Rear seat DVD entertainment and the Lexus Night View System are optional. The LX 470 houses a 4.7 liter V-8 inside its rugged body-on-frame construction. The V-8 is enhanced by Toyota's Variable Valve Timing + intelligence technology, which boost engine output while improving fuel economy and lowering emissions. The 5590 lb. LX receives 268 horsepower and 328 pound-feet of torque, which is enough power to pull 6500 additional pounds. The engine is paired with an electronically-controlled five-speed automatic transmission. Drivers can expect gas mileage of 13/17 mpg.
We recently replaced the power steering pump & the serpentine belt on a 2007 Lexus LX470. Now, when we try to make a hard turn, the steering will intermittently lock up. Any ideas? We replaced the fluid.
Air Conditioning
Active charcoal air filtration · Automatic climate control front air conditioning · Single front air conditioning zones · Automatic climate control rear air conditioning · Single rear air conditioning zones
Airbags
Dual front airbags · Passenger airbag deactivation: occupant sensing deactivation · Front side airbags · Rear side curtain airbags
Audio System
Antenna Type: diversity · CD changer: 6 · Wireless headphones · In-Dash CD: DVD · Premium Brand: Mark Levinson · AM/FM radio · Rear audio: separate rear audio · Remote CD changer location: in center console · Sirius Satellite Radio · 1 subwoofer · Total Number of Speakers: 11 · 240 watts
Brakes
ABS: 4-wheel · Front brake diameter: 12.2 · Front brake width: 1.3 · Front brakes: ventilated disc · Rear brake diameter: 12.8 · Rear brake width: 0.7 · Rear brakes: ventilated disc
Comfort Features
Center console trim: leather · Dash trim: wood · Door trim: wood · Floor Mat Material: carpet · Floor Mats: front · Shift knob trim: wood · Steering wheel trim: wood
Convenience Features
Cargo area power outlet: 12V · Center console: front console with storage · Cupholders: rear · Dimming rearview mirror: auto-dimming · Easy entry: power steering wheel · Memorized settings: 2 driver · Multi-function remote: keyless entry · One-touch windows: 4 · Power outlet(s): 12V front · Power steering: speed-proportional · Reading lights: front · Steering wheel: tilt and telescopic · Steering wheel mounted controls: audio · Storage: front seatback · Vanity mirrors: dual illuminating
Driver Seat
Adjustable lumbar support: power · Power adjustments: 10
Drivetrain
4WD Type: full time · Axle ratio: 4.10 · Locking differential: center · Transfer Case: manual hi-lo gear selection
Exterior Features
Door handle color: chrome · Grille color: chrome · Rear trunk/liftgate: liftgate
Headrests
Front headrests: adjustable · Number of front headrests: 2 · Number of rear headrests: 3 · Number of third row headrests: 2
In Car Entertainment
Video monitor location: rear · Video monitor size: 6.5 · Video system: DVD player
Instrumentation
Warnings and reminders: low fuel level
Lights
Exterior entry lights: security approach lamps · Headlights: auto delay off · Tail and brake lights: rear center brakelight
Mirrors
Exterior mirrors: power folding
Passenger Seat
Adjustable lumbar support: power · Power adjustments: 10
Rear Seats
Type: 60-40 split bench
Roof
Moonroof: power glass · Roof rack: with crossbars · Sunroof: wind deflector
Safety
Camera system: rearview · Rearview monitor: in dash
Seatbelts
Rear center seatbelt: 3-point · Seatbelt force limiters: front · Seatbelt pretensioners: front
Seats
Driver seat power adjustments: reclining · Front seat type: bucket · Passenger seat power adjustments: reclining · Rear headrests: adjustable · Rear seat folding: split · Rear seat manual adjustments: reclining · Third row seat folding: split · Upholstery: leather
Spare Tire
Mount Location: underbody
Spare Wheel
Rim type: aluminum alloy
Suspension
Driver Adjustable Suspension: height · Front Shock Type: gas shock absorbers · Front Spring Type: torsion bars · Front Suspension Classification: independent · Front Suspension Type: double wishbones · Leveling: self leveling suspension · Rear Shock Type: gas shock absorbers · Rear Spring Type: coil springs · Rear Suspension Classification: solid live axle · Rear Suspension Type: multi-link · Stabilizer bar(s): rear · Suspension control: electronic
Telematics
Navigation system: DVD navigation system · Phone wireless data link: Bluetooth
Third Row Seat
Type: removable split-bench
Tires
Type: all season
Tires and Rims
Spare tire size: full-size matching
Wheels
Width: 8
Windows
Front wipers: rain sensing · Liftgate window: fixed · Power windows: remote operation · Rear quarter windows: power · Rear wiper: intermittent