Overview
The Corris Rivett suspension system is engineered for the classic rear-wheel-drive platform. Understanding these components is critical for both assembly and winter driving dynamics. The front uses MacPherson struts while the rear features a sophisticated 4-link solid axle design.
Unlike modern cars with electronic stability systems, the Rivett relies entirely on mechanical suspension geometry to handle the icy Finnish roads. Proper assembly and maintenance of these components directly affects your survival.
Front Suspension: MacPherson Strut
Overview
The MacPherson strut design combines the shock absorber and coil spring into a single unit, reducing complexity and weight.
Key Components
| Component | Function | |-----------|----------| | Strut Assembly | Absorbs impacts, supports spring | | Lower Control Arm | Controls wheel position | | Ball Joint | Allows steering pivot | | Anti-Roll Bar | Reduces body lean |
Strut Assembly
The strut mounts to:
- Top: Strut tower in engine bay (3x 10mm nuts)
- Bottom: Steering knuckle/spindle (2x 17mm bolts)
Wear Signs:
- Bouncing after bumps = worn shock
- Oil leaking from strut body = seal failure
- Clunking over bumps = loose top mount
Front Lower Control Arm
| Aspect | Detail | |--------|--------| | Mounting | Subframe via 17mm bolts | | Function | Controls track width and camber | | Bushings | Rubber, wear out over time |
Worn Bushing Symptoms:
- Vague steering feel
- Clunking during braking
- Uneven tire wear
Anti-Roll Bar (Sway Bar)
- Connects left and right suspension
- Reduces body roll in corners
- Improves high-speed stability
- Bolt Size: 13mm
Rear Suspension: 4-Link Solid Axle
Overview
The Rivett's rear uses a live axle design with 4-link geometry. This is a significant upgrade over simple leaf springs, offering better handling and axle control.
4-Link Geometry Explained
| Arms | Function | |------|----------| | Lower Control Arms (x2) | Long arms that locate axle front-to-back | | Upper Control Arms (x2) | Angled arms that prevent rotation and side movement |
The angled upper arms act like a Panhard rod, keeping the axle centered under the car.
Rear Lower Control Arms
| Aspect | Detail | |--------|--------| | Quantity | 2 (left and right) | | Bolt Size | 17-19mm | | Wearable | Yes (bushings) | | Function | Longitudinal axle location |
Rear Upper Control Arms
| Aspect | Detail | |--------|--------| | Quantity | 2 (left and right) | | Bolt Size | 17mm | | Wearable | Yes (bushings) | | Function | Prevents axle rotation under torque |
The "Rear Axle Steering" Problem
CRITICAL FOR WINTER DRIVING:
Worn bushings in the control arms allow the rear axle to shift left/right during:
- Acceleration (axle twists one way)
- Braking (axle twists opposite way)
This causes the rear of the car to "steer itself" - extremely dangerous on ice where small movements cause slides!
Coil Springs & Shocks
| Component | Location | Notes | |-----------|----------|-------| | Rear Coil Spring | Spring perch | Supports vehicle weight | | Rear Shock | Axle to chassis | Bolt: 13mm, wearable |
Shock Wear Signs:
- Excessive bouncing
- Poor ride quality
- Bottoming out on bumps
Differential
Location
The differential sits in the center "pumpkin" of the rear axle assembly.
Types
| Type | Description | Winter Performance | |------|-------------|-------------------| | Open Differential | Standard, power goes to wheel with least resistance | Poor - one wheel spins, other stays still | | Limited Slip (LSD) | Locks wheels together partially | Excellent - both wheels provide traction |
Determining Your Diff Type
- Base/L trim: Usually open differential
- GT trim: May have LSD standard
- Check VIN: Decode for factory options
LSD Advantage in Winter
With an open diff in snow:
- One wheel loses traction
- All power goes to that wheel
- It spins uselessly
- You're stuck
With LSD:
- One wheel loses traction
- Diff transfers torque to other wheel
- Both wheels push
- You keep moving
Steering System
Rack and Pinion
| Component | Bolt Size | Notes | |-----------|-----------|-------| | Steering Rack | 14mm | Mounts to subframe | | Tie Rod Ends | 17mm | Connect to spindles |
Tie Rod Wear
Symptoms:
- Play in steering wheel
- Wandering at highway speeds
- Uneven tire wear
- Clunking when turning
Brake System
Front Brakes: Disc
| Component | Bolt Size | Wearable | |-----------|-----------|----------| | Brake Disc | Wheel studs | Yes - warps if overheated | | Brake Caliper | 13mm | Yes - seizes if rusted | | Brake Pads | Clips | Yes - friction wears |
Rear Brakes: Drum
| Component | Wearable | Notes | |-----------|----------|-------| | Brake Drum | Yes | Check for scoring | | Brake Shoes | Yes | Require periodic adjustment | | Wheel Cylinder | Yes | Hydraulic, can leak |
Brake Hydraulics
| Component | Location | Bolt Size | |-----------|----------|-----------| | Master Cylinder | Firewall | 13mm | | Brake Lines | Chassis | 10-11mm | | Banjo Bolts | Calipers | 11mm |
Fluid Leak Signs:
- Soft/spongy pedal
- Pedal sinks to floor
- Clear/yellow puddle under car
- Warning light on dash
Brake Bleeding
After any hydraulic work, you must bleed air from the system:
- Start at wheel furthest from master cylinder
- Open bleeder valve
- Pump pedal, hold down
- Close valve
- Repeat until no bubbles
Tires & Wheels
Winter Tire Requirements
| Specification | Recommendation | |---------------|----------------| | Type | Studded winter tires | | Size | 13-inch (OEM) | | Pressure | Reduce 2-3 PSI for snow | | Studs | Essential for ice grip |
Tire Wear Indicators
- Center wear: Over-inflation
- Edge wear: Under-inflation
- Cupping: Worn shocks
- One-side wear: Alignment issue
Studded vs Non-Studded
| Type | Ice Grip | Road Noise | Legality | |------|----------|------------|----------| | Studded | Excellent | Loud | Check local laws | | Non-Studded | Poor on ice | Quiet | Always legal |
For My Winter Car: Studded tires are effectively mandatory for survival.
Suspension Noises Diagnostic
| Sound | Location | Likely Cause | |-------|----------|--------------| | Clunk over bumps | Front | Loose strut mounts (10mm) | | Squeak while turning | Front | Dry ball joints | | Thud during braking | Rear | Worn control arm bushings | | Rear "wandering" | Rear | Axle shifting (bushing wear) | | Constant vibration | Driveshaft | Worn U-joints |
Assembly Tips
Torque Specifications
| Component | Bolt Size | Torque (est.) | |-----------|-----------|---------------| | Strut top mount | 10mm | 25 Nm | | Strut to spindle | 17mm | 100 Nm | | Control arm | 17mm | 90 Nm | | Rear links | 17-19mm | 100-120 Nm | | Wheel nuts | Varies | 80-100 Nm |
Alignment Considerations
After suspension work, wheel alignment may be needed:
- Camber: Angle of wheel vs vertical
- Toe: Wheels pointing in/out
- Caster: Steering axis angle
Improper alignment causes:
- Tire wear
- Pulling to one side
- Poor handling
Winter Handling Dynamics
RWD Oversteer
The Rivett's rear-wheel-drive layout creates natural oversteer - the rear loses grip before the front.
| Situation | Response | |-----------|----------| | Rear slides out | Counter-steer (turn into slide) | | Too much throttle | Lift off gently | | Ice patch | Steady inputs, no sudden moves |
Weight Transfer
| Action | Weight Shift | Effect | |--------|--------------|--------| | Accelerate | To rear | More rear grip, less front | | Brake | To front | More front grip, less rear | | Turn | To outside | Outside tires grip more |
Sandbag Strategy
Add sandbags in the trunk over the rear axle:
- Increases rear tire grip
- Improves straight-line traction
- Trade-off: Heavier car harder to stop/turn
Recommended: 2-4 sandbags for winter driving.
Maintenance Schedule
Weekly Checks
- Tire pressure
- Brake fluid level
- Visual suspension inspection
- Unusual noises
Monthly
- Inspect brake pads/shoes
- Check for fluid leaks
- Test shock absorbers (bounce test)
- Lubricate ball joints (if equipped)
Seasonal
- Full brake inspection
- Bushing condition check
- Alignment verification
- Tire swap (winter/summer)
Rear Axle Steering
Worn rear control arm bushings cause the axle to shift left/right during acceleration or braking. This makes the car unpredictable on ice - it steers from the rear!
LSD for Winter
A Limited Slip Differential (LSD) is vastly superior for winter driving. Both wheels spin together, providing traction in snow. Check your trim level - GT models may have LSD standard.