Performance Steering Brands and Upgrades - Square Body Trucks

Overview

Performance steering upgrades are among the most impactful modifications you can make to a 1973-1987 GM Square Body truck. The factory steering systems, while adequate for their era, suffer from excessive play, poor road feel, and vague on-center response by modern standards. This comprehensive guide covers aftermarket steering box upgrades, power steering pump improvements, and complete steering system overhauls that will transform your Square Body's driving experience.

Whether you're building a pro-touring C10, restoring a K20 4x4, or simply want better control of your daily-driven Suburban, understanding the available performance steering options is crucial. Modern steering upgrades can reduce steering wheel play from 3-4 inches down to less than 1 inch, improve highway stability, and provide the precise control needed for performance driving.

Common Issues

Factory Steering System Problems

Excessive Steering Play
- Factory Saginaw 605 steering boxes typically develop 15-20 degrees of play at the steering wheel
- Worn sector shaft bushings and internal components create dead spots
- Problem worsens with age and mileage, especially in 4WD models

Poor Road Feel and Feedback
- Over-assisted power steering masks road conditions
- Vague on-center feel makes highway driving tiring
- Difficult to detect traction limits during performance driving

Wandering and Instability
- Worn steering components cause vehicle to wander at highway speeds
- Requires constant steering corrections
- Amplified by worn suspension components and alignment issues

Inadequate Performance for Modified Vehicles
- Factory steering ratios too slow for performance applications
- Power assistance levels inappropriate for wider tires and performance suspensions
- Steering boxes cannot handle increased loads from performance modifications

Parts & Materials Needed

Performance Steering Boxes

Borgeson Universal (Premium Choice)
- 911014 - 12.7:1 ratio box for 1973-1987 (most popular)
- 911013 - 16:1 ratio box for heavy-duty applications
- 911015 - 10.5:1 ratio box for maximum performance
- Price range: $650-$750

Redhead Steering Gears (High Performance)
- RH-7387-C10 - Stage 2 performance box, 12.7:1 ratio
- RH-7387-K10 - Heavy-duty box for 4WD applications
- RH-7387-RACE - Competition box with 10:1 ratio
- Price range: $550-$650

CPP (Classic Performance Products)
- 6466SB-1 - Performance steering box kit with all hardware
- 6466SB-HD - Heavy-duty version for lifted trucks
- Price range: $450-$550

AGR Performance (Remanufactured OEM+)
- AGR-SB7387 - Rebuilt Saginaw 605 with performance internals
- AGR-SB7387-HD - Heavy-duty version with upgraded components
- Price range: $350-$450

Power Steering Pumps

Saginaw P-Series (High Flow)
- 7837645 - High-flow pump for 1973-1980 applications
- 14044597 - High-pressure pump for 1981-1987 applications
- Flow rate: 3.5 GPM vs 2.5 GPM factory

Borgeson Power Steering Pumps
- 800322 - High-performance pump with integral reservoir
- 800323 - Remote reservoir version for clearance issues
- Pressure rating: 1,500 PSI vs 1,200 PSI factory

CPP LS-Series Conversion Pumps
- LSP-001 - LS1 pump conversion kit
- LSP-002 - LS3/LS7 high-flow pump kit
- Required for LS engine swaps

Installation Hardware and Components

Steering Shafts and Joints
- Borgeson 000934 - Universal joint kit
- Flaming River FR1590 - Steering shaft assembly
- Ididit 1140 - Tilt column conversion shaft

Mounting Hardware
- Grade 8 bolts and washers for steering box mounting
- Red Loctite 271 for critical fasteners
- Anti-seize compound for adjusters

Fluids and Seals
- Lucas Power Steering Fluid or Valvoline MaxLife ATF
- Steering box seals and gaskets (included with most kits)
- High-temperature thread sealant

Step-by-Step Installation Guide

Pre-Installation Preparation

1. Vehicle Preparation
   - Raise vehicle on level surface using proper jack stands
   - Remove front wheels and inspect suspension components
   - Mark steering wheel center position with tape
   - Disconnect battery negative terminal

2. Fluid Drainage
   - Remove power steering reservoir cap
   - Disconnect return line and drain fluid into container
   - Remove pressure line and allow remaining fluid to drain

Steering Box Removal

3. Disconnect Steering Components
   - Remove cotter pin from pitman arm nut
   - Use pitman arm puller to separate arm from sector shaft
   - Critical: Mark pitman arm position on sector shaft

4. Remove Steering Shaft Connection
   - Remove pinch bolt from steering shaft coupling
   - Separate coupling from steering box input shaft
   - Support steering column to prevent damage

5. Unbolt Steering Box
   - Remove three mounting bolts (typically 9/16" or 14mm)
   - Support steering box weight during removal
   - Clean mounting surface thoroughly

Performance Steering Box Installation

6. Install New Steering Box
   - Apply thread locker to mounting bolts
   - Torque mounting bolts to 85 ft-lbs in sequence
   - Ensure proper alignment with frame rails

7. Connect Steering Shaft
   - Align steering box input shaft with coupling
   - Install pinch bolt and torque to 35 ft-lbs
   - Verify no binding through full steering range

8. Install Pitman Arm
   - Align pitman arm with marked position on sector shaft
   - Install pitman arm nut and torque to 185 ft-lbs
   - Install new cotter pin

Power Steering System Connection

9. Connect Hydraulic Lines
   - Install pressure line with new O-ring seals
   - Torque pressure fitting to 25 ft-lbs (do not overtighten)
   - Connect return line with new clamps

10. Fill and Bleed System

    • Fill reservoir with specified power steering fluid
    • Start engine and turn steering wheel lock-to-lock 10 times
    • Check fluid level and top off as needed
    • Verify no leaks at all connections

Final Adjustments

11. Steering Box Adjustment

    • Locate adjustment screw on top of steering box
    • Turn clockwise 1/4 turn from factory setting
    • Test for proper feel without binding
    • Warning: Over-adjustment will cause premature wear

12. Alignment Check

    • Verify steering wheel is centered when driving straight
    • Schedule professional alignment within 100 miles
    • Check toe settings as steering box changes may affect alignment

Year and Model Differences

1973-1980 Models

Steering Box Mounting
- Uses three-bolt pattern with 4.75" bolt spacing
- Mounting bolts are 9/16"-18 thread
- Pitman arm has 1.25" diameter sector shaft

Power Steering System
- Uses Saginaw Type II pump with integral reservoir
- Pressure line uses 5/8"-18 O-ring fitting
- Return line is 5/8" ID rubber hose with clamps

Column Integration
- Steering shaft uses single universal joint
- Column drop varies by cab configuration
- Tilt columns require specific shaft lengths

1981-1987 Models

Updated Mounting Design
- Same bolt pattern but updated hardware
- Improved sector shaft sealing design
- Better corrosion resistance on mounting surfaces

Hydraulic System Changes
- Higher pressure pump standard (1,200 PSI vs 1,000 PSI)
- Updated fitting designs with better sealing
- Improved reservoir design with integral filter

Electronic Integration
- Some 1987 models have provisions for future electronic systems
- Wiring harness routing considerations for aftermarket boxes
- Cruise control compatibility maintained with proper installation

Model-Specific Considerations

C10/C20 2WD Applications
- Lower steering box position due to frame design
- Shorter pitman arm standard (5.5" vs 6.0" on 4WD)
- Easier access for installation and maintenance

K10/K20 4WD Applications
- Higher steering box mounting for ground clearance
- Longer pitman arm to clear front differential
- Additional stress from 4WD operation requires heavy-duty components

K5 Blazer and Suburban
- Same mounting as pickup trucks
- Shorter wheelbase affects steering response characteristics
- Higher center of gravity benefits more from performance steering upgrades

Tips and Best Practices

Selection Guidelines

Ratio Selection for Intended Use
- 16:1 Ratio: Best for heavy trucks, towing, and off-road use
- 12.7:1 Ratio: Ideal balance for street performance and daily driving
- 10.5:1 Ratio: Maximum performance for autocross and road racing

Quality Considerations
- Avoid cheap imported steering boxes - they often fail quickly
- Borgeson and Redhead offer the best combination of performance and reliability
- Remanufactured units can be good value if from reputable sources

Installation Best Practices

Preparation Steps
- Always replace pitman arm if worn or damaged
- Inspect tie rod ends and center link before installation
- Consider upgrading to performance tie rod ends simultaneously

Torque Specifications
- Never exceed specified torque values on hydraulic fittings
- Use calibrated torque wrench for all critical fasteners
- Apply thread locker to prevent loosening from vibration

Break-In Procedure
- Drive gently for first 100 miles after installation
- Check fluid level after first few drives
- Retorque mounting bolts after 500 miles

Common Mistakes to Avoid

Over-Adjustment
- Most common cause of premature steering box failure
- Start with minimal adjustment and fine-tune gradually
- Binding feel indicates over-adjustment

Improper Fluid Selection
- Use only manufacturer-recommended fluids
- ATF Dexron III is acceptable substitute for most applications
- Avoid mixing different fluid types

Alignment Neglect
- Always check alignment after steering box replacement
- Toe settings are most critical for tire wear
- Caster adjustments may improve highway stability

Troubleshooting

Performance Issues

Steering Still Has Excessive Play
- Check pitman arm to sector shaft connection
- Inspect tie rod ends and center link for wear
- Verify proper steering box adjustment

Heavy Steering Effort
- Check power steering fluid level and condition
- Test power steering pump pressure (should be 1,200+ PSI)
- Inspect for kinked or damaged hydraulic lines

Steering Wander or Instability
- Verify proper wheel alignment, especially toe settings
- Check tire pressures and tread condition
- Inspect suspension components for wear

Hydraulic System Problems

Power Steering Fluid Leaks
- Most common at pressure line O-ring seals
- Check steering box input shaft seal
- Inspect pump mounting and reservoir connections

Noisy Power Steering Operation
- Usually indicates low fluid level or aerated fluid
- Bleed system thoroughly by cycling steering lock-to-lock
- Check for loose suction line connections

Intermittent Power Assist
- Often caused by slipping pump drive belt
- Check belt tension and condition
- Verify pump mounting bracket integrity

Mechanical Issues

Steering Binding or Stiffness
- Check for over-adjustment of steering box
- Inspect universal joints for proper lubrication
- Verify steering column alignment

Steering Wheel Not Centered
- Adjust tie rod lengths equally to center steering wheel
- Check for bent or damaged steering components
- Professional alignment may be required

Premature Component Wear
- Usually indicates improper installation or adjustment
- Check mounting bolt torque and thread locker application
- Verify compatibility of all system components

Performance steering upgrades represent one of the most cost-effective modifications for Square Body trucks, dramatically improving both safety and driving enjoyment. When properly selected and installed, these systems will provide decades of reliable service while transforming your truck's road manners from vague and wandering to precise and confidence-inspiring.