QA1 78-96 GM B-Body Pro Rear Coil-Over System - Double Adjustable - 12in x 250 lb/in - Aluminum
The QA1 RCK52380 Pro Rear Coil-Over Conversion System is the ultimate bolt-in upgrade for your 1978-1996 GM B-Body (Caprice, Impala, etc.). This complete system replaces the factory leaf springs with modern double-adjustable aluminum coil-overs featuring 250 lb/in springs, giving you 2.5" to 5.5" of adjustable rear drop, vastly improved ride quality, and superior handling. With independent compression and rebound adjustment (18 positions each, for 324 possible combinations), you can fine-tune the suspension for daily driving, cruising, or aggressive cornering while dramatically reducing unsprung weight and eliminating the harsh ride of stock leaf springs.
Key Features
- Double Adjustable Shocks: 18 positions of compression + 18 positions of rebound (324 possible valving combinations)
- 250 lb/in High-Travel Springs: Lighter medium rate optimized for street-driven and performance B-Body builds
- 12" Spring Length: Ideal for lowered applications with excellent travel
- Fully Threaded Aluminum Body: Easy ride height adjustment from 2.5" to 5.5" drop
- Bolt-In Conversion: Direct replacement for factory leaf springs no cutting or welding
- Lightweight & Durable: Reduces unsprung weight while maintaining strength
Specifications
| Specification | Detail |
|---|---|
| Part Number | RCK52380 |
| Position | Rear |
| Shock Type | Double Adjustable Aluminum Coil-Over |
| Spring Rate | 250 lb/in |
| Spring Length | 12" |
| Drop Range | 2.5" - 5.5" |
| Compatibility | 1978-1996 GM B-Body (Chevrolet Caprice, Impala, Buick, Oldsmobile, Pontiac) |
| Installation | Bolt-On Coil-Over Conversion |
| Country of Origin | United States |
| Warranty | Limited Lifetime (QA1) |
| Shipping Weight | Approx. 55-65 lbs |
What's Included
- Pair of QA1 Double Adjustable Aluminum Rear Coil-Over Shocks
- Pair of 12" x 250 lb/in High-Travel Springs
- Specially Designed USA-Made Mounting Brackets
- All Necessary Hardware & U-Bolts
- Detailed Installation Instructions
Product Notes
- Designed for 1978-1996 GM B-Body vehicles (Caprice, Impala, etc.)
- Later model B-Bodies tend to weigh more contact QA1 tech for spring rate questions
- Professional installation and rear alignment recommended
Installation Notes
- Estimated time: 6-10 hours, moderate to advanced difficulty
- Bolt-on conversion removes factory leaf springs and installs coil-overs
- Full rear alignment and driveline angle check required after installation
This Part Fits
| Year | Make | Model | Notes |
|---|---|---|---|
| 1978 to 1996 | Chevrolet | Caprice / Impala | All B-Body Configurations (Sedan, Wagon) |
| 1978 to 1996 | Buick | LeSabre / Roadmaster | B-Body Models |
| 1978 to 1996 | Oldsmobile | Delta 88 / Ninety-Eight | B-Body Models |
| 1978 to 1996 | Pontiac | Bonneville / Parisienne | B-Body Models |
Why Choose QA1 Rear Coil-Over Conversion System?
- Modern coil-over performance with classic B-Body styling and stance
- Full adjustability for the perfect ride height and handling balance
- Premium QA1 quality with lifetime warranty confidence
Frequently Asked Questions
-
Q: Will this kit fit my 1995 Chevrolet Caprice?
A: Yes, RCK52380 is a direct fit for all 1978-1996 GM B-Body vehicles. -
Q: What spring rate is included?
A: 250 lb/in lighter medium rate ideal for most street-driven B-Bodies. -
Q: Is an alignment required?
A: Yes, a full rear alignment is required after installation. -
Q: What is the warranty?
A: Covered by QA1’s limited lifetime warranty.
Shipping & Handling
- Method: UPS / FedEx Ground (Oversize)
- Availability: In stock ships same or next business day
- Packaging: Secure protective packaging
- Weight: Approx. 55-65 lbs
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