Overview
Steering upgrades for 1973-1987 GM Square Body trucks represent one of the most impactful improvements an owner can make to their vehicle's drivability and safety. The factory steering systems, while adequate for their time, suffer from excessive play, poor road feel, and component wear that becomes pronounced as these trucks age. Modern steering upgrades can transform a wandering, loose-feeling truck into a precise, confidence-inspiring machine.
This comprehensive guide covers power steering box upgrades, steering shaft improvements, tie rod and linkage upgrades, and complete steering system overhauls for C10, C20, K10, K20, K5 Blazer, and Suburban models. Whether you're dealing with a worn-out original system or planning a complete restoration, understanding these upgrades will help you choose the right approach for your needs and budget.
Common Issues
Square Body truck owners typically encounter several steering-related problems that worsen over time:
Excessive Play and Wandering
- Steering box wear: Internal components develop play, requiring constant correction
- Worn tie rod ends: Create loose, imprecise steering feel
- Pitman arm wear: Develops play at the steering box connection
- Idler arm deterioration: Causes steering wander and uneven tire wear
Power Steering Problems
- Pump failure: Original pumps develop internal leakage and noise
- Hose deterioration: 40+ year old hoses leak and restrict flow
- Steering box leakage: Seals fail, causing fluid loss and reduced assist
Steering Shaft Issues
- Rag joint deterioration: Rubber coupling fails, creating play and vibration
- U-joint wear: Develops binding and play in steering column
- Column bearing wear: Creates loose feel and potential safety issues
Parts & Materials Needed
Power Steering Box Options
Budget Option - Remanufactured Stock Boxes:
- 7838 7831 455 - 1973-1976 C/K series standard ratio
- 7838 7832 455 - 1977-1987 C/K series standard ratio
- Available from AutoZone, O'Reilly's ($150-200 core exchange)
Performance Upgrade - Redhead Steering Boxes:
- Redhead Classic - Rebuilt with improved seals and tighter tolerances
- Redhead Stage 2 - Modified for reduced play and improved feel
- Redhead Stage 3 - Competition-grade with maximum precision
- Available from Redhead Steering Gears ($400-800 depending on stage)
Premium Option - Borgeson Steering Boxes:
- 999-0134 - Direct replacement for 1973-1987 trucks
- Features modern sealing technology and precision machining
- Available from Summit Racing, Jegs ($600-900)
Steering Linkage Components
Complete Tie Rod Assembly:
- ES3382RL - Moog outer tie rod ends (left/right pair)
- ES3008 - Moog inner tie rod ends
- DS1161 - Moog center link
- K6141 - Moog pitman arm
- K6142 - Moog idler arm
Premium Linkage Options:
- Cognito Heavy Duty Kit - Forged components for lifted trucks
- Kryptonite Lifetime Kit - Greaseable, rebuildable components
- Available from LMC Truck, Classic Performance Products
Steering Shaft Upgrades
Borgeson Universal Steering Shafts:
- 000913 - 1973-1980 trucks with manual steering
- 000914 - 1973-1980 trucks with power steering
- 000915 - 1981-1987 trucks (all applications)
- Features replaceable U-joints and eliminates rag joint
Flaming River Steering Columns:
- Complete tilt and non-tilt column replacements
- Modern bearings and improved ergonomics
- Available in original and custom lengths
Power Steering Pump Options
Stock Replacement:
- 7840 368 - 1973-1980 small block applications
- 7840 400 - 1973-1987 big block applications
- Available from most parts stores ($80-120 rebuilt)
Performance Upgrades:
- AGR High Flow Pump - Increased flow for larger tires
- PSC Motorsports Pump - Competition-grade reliability
- Saginaw TC Series - Modern pump with improved efficiency
Tools and Materials Required
Essential Tools:
- Pitman arm puller
- Tie rod end separator (pickle fork or ball joint separator)
- Torque wrench (capable of 180+ ft-lbs)
- Standard socket set (SAE sizes)
- Power steering fluid (Dexron III/Mercon or equivalent)
Specialty Tools:
- Steering box puller (for removal)
- Pressure washer (for cleaning)
- Thread locker (blue Loctite 242)
Step-by-Step Guide
Phase 1: Assessment and Planning
-
Evaluate Current System
- Check steering play (should be less than 2 inches at rim)
- Inspect all components for wear, damage, or leakage
- Test drive to identify specific problems -
Choose Upgrade Path
- Basic refresh: Replace worn components with OEM equivalents
- Performance upgrade: Install improved steering box and linkage
- Complete overhaul: Replace entire system with modern components
Phase 2: Steering Box Replacement
-
Preparation
- Disconnect battery negative terminal
- Raise front of vehicle and secure on jack stands
- Center steering wheel and mark position -
Remove Old Steering Box
Torque specifications for removal: - Pitman arm nut: 180 ft-lbs (reverse to remove) - Steering box mounting bolts: 65 ft-lbs - Steering shaft coupling: 35 ft-lbs -
Install New Steering Box
- Mount box to frame with new hardware
- Connect steering shaft (ensure proper alignment)
- Install pitman arm with proper timing marks aligned
- Torque all fasteners to specification
Phase 3: Linkage Replacement
-
Remove Old Components
- Use proper pullers to avoid damage
- Mark alignment of adjusting sleeves before removal
- Clean all mounting points thoroughly -
Install New Linkage
- Install components in reverse order of removal
- Use new cotter pins and hardware throughout
- Set initial toe adjustment using old measurements
Phase 4: Power Steering System Service
-
Pump and Hose Replacement
- Drain system completely
- Replace pump, hoses, and cooler (if equipped)
- Use proper routing to avoid heat sources -
System Fill and Bleed
- Fill reservoir with specified fluid
- Turn steering lock-to-lock with engine off
- Start engine and repeat process until air is eliminated
- Check for leaks and proper operation
Year/Model Differences
1973-1980 vs 1981-1987 Distinctions
Early Models (1973-1980):
- Use different steering shaft configurations
- Manual steering available on base models
- Different power steering pump mounting
- Require specific Borgeson shaft part numbers
Late Models (1981-1987):
- Standardized on power steering across most models
- Improved column design with better bearings
- Different steering box mounting bolt pattern on some applications
- Enhanced power steering pump efficiency
Model-Specific Considerations
C10/C20 (2WD Models):
- Lower ride height affects steering geometry
- Different pitman arm angles compared to 4WD
- May require different tie rod lengths for lifted applications
K10/K20 (4WD Models):
- Higher steering box mounting position
- Different front axle geometry affects alignment
- May require heavy-duty components for off-road use
K5 Blazer Specific:
- Shorter wheelbase affects steering response
- Same components as K10 but different handling characteristics
- Consider heavy-duty upgrades for off-road applications
Suburban Applications:
- Longer wheelbase provides more stable steering
- Same basic components as pickup trucks
- May benefit from heavy-duty upgrades due to vehicle weight
Tips & Best Practices
Installation Best Practices
Proper Torque Specifications:
- Always use a calibrated torque wrench for critical fasteners
- Apply thread locker to steering box mounting bolts
- Replace all cotter pins and safety hardware
Alignment Considerations:
- Mark original tie rod positions before disassembly
- Have professional alignment performed after installation
- Check alignment again after 500 miles of driving
Fluid and Maintenance:
- Use only specified power steering fluid
- Change fluid every 50,000 miles or 5 years
- Inspect system annually for leaks and wear
Common Mistakes to Avoid
Installation Errors:
- Never reuse old cotter pins or castle nuts
- Don't overtighten tie rod adjusting sleeves
- Avoid using impact guns on steering box mounting bolts
Component Selection:
- Don't mix steering ratios (fast vs. slow)
- Avoid cheap overseas tie rod ends
- Don't ignore power steering pump compatibility
Maintenance Oversights:
- Don't ignore small leaks (they become big problems)
- Don't skip the break-in period for new components
- Don't delay addressing steering problems
Troubleshooting
Persistent Steering Play
Symptoms: Excessive play remains after component replacement
Causes:
- Worn steering box internal components
- Improper pitman arm installation
- Frame damage or cracking
Solutions:
- Verify proper pitman arm timing
- Inspect frame mounting points for damage
- Consider upgraded steering box with tighter tolerances
Power Steering Issues
Hard Steering:
- Check belt tension and condition
- Verify proper fluid level and type
- Test pump pressure (should be 1200-1500 PSI)
Steering Wander:
- Inspect tire pressure and condition
- Check front end alignment
- Verify proper caster and camber settings
Noise and Vibration:
- Bleed air from power steering system
- Check for loose or damaged mounting hardware
- Inspect steering shaft U-joints for wear
Post-Installation Problems
Steering Pull:
- Verify equal tire pressures
- Check for bent or damaged components
- Have alignment checked professionally
Excessive Effort:
- Confirm proper power steering operation
- Check for binding in steering linkage
- Verify correct steering box installation
Premature Wear:
- Check alignment specifications
- Inspect suspension components
- Verify proper lubrication of grease fittings
Modern steering upgrades can dramatically improve the driving experience of Square Body trucks while enhancing safety and reducing driver fatigue. Choose components appropriate for your intended use, follow proper installation procedures, and maintain the system regularly for optimal performance and longevity.