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SKU: LSD 180 C15 | UPC: 4996338017017
Cusco LSD RS1.5WAY (1 & 1.5) Front Differential for GC8 GDA Subaru Impreza BR9 BM9 1993-2007
Cusco LSD RS1.5WAY front limited slip differential installs directly into Subaru Impreza GC8 and GDA chassis with BR9 BM9 front differentials. Built for WRX STI and WRX models it provides full lock during acceleration for maximum power to both wheels. Partial lock on deceleration keeps stability in corners for road or track driving.
Key Features
- 1.5 Way Action: Full lock under acceleration transfers torque instantly partial lock on deceleration prevents inside wheel spin
- Clutch Pack Design: 6 clutch plates per side deliver consistent grip under high load conditions
- WPC Processed Gears: Shot peened bevel gears cut wear by 30% and lower operating temperatures for long service life
- Fixed Preload Setting: Factory set initial torque at 55-65% ensures predictable response without adjustments
- Made in Japan: Forged internals handle 500+hp builds with direct OEM replacement fit
Product Notes
- Pair with Cusco LSD oil Type-RS for clutch protection and smooth operation
- Perform 30 minute break-in at 50% throttle after install
- Heavy item ships freight or UPS oversized rate applies
Installation Notes
- Professional installation recommended.
- Remove front differential drain fluid and replace crush washers
- Bolts directly to OEM carrier case no modifications needed
This Part Fits
| Year | Make | Model | Submodel |
|---|---|---|---|
| 2004-2007 | Subaru | Impreza | WRX STI |
| 2007 | Subaru | Impreza | WRX STI Limited |
| 2006-2007 | Subaru | Impreza | WRX TR |
| 2006-2007 | Subaru | Impreza | 2.5i |
| 2001 | Subaru | Impreza | L |
| 2001-2004 | Subaru | Impreza | Outback |
| 2005-2007 | Subaru | Impreza | Outback Sport |
| 2001-2005 | Subaru | Impreza | RS |
| 2002-2004 | Subaru | Impreza | TS |
| 2002-2007 | Subaru | Impreza | WRX |
| 2006-2007 | Subaru | Impreza | WRX Limited |
| 1993-2000 | Subaru | Impreza | GC8 WRX STI |
| 2002-2007 | Subaru | Impreza | GDA STI BR9 BM9 |
Why Choose Cusco?
- Motorsport pedigree from rally and drift championships
- Direct fit engineering from OEM supplier standards
- Components tested to 100000km durability
Frequently Asked Questions
-
Q: Will this fit 2004-2007 USDM WRX STI?
A: Yes LSD 180 C15 bolts into BR9 front diff housing on 2004-2007 STI models -
Q: What gear oil works best?
A: Use Cusco LSD oil Type-RS 75W-140 synthetic 1.1 quarts fills front diff -
Q: Is professional install required?
A: Recommended due to axle shaft alignment and preload shimming during assembly
Shipping & Handling
- Method: UPS Ground or Freight for heavy item
- Availability: In stock - ships same or next business day
- Packaging: Double wall carton 14 x 14 x 10 inches
- Weight: 25 lbs
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Cusco is a Japanese performance parts manufacturer with over 40 years of motorsports experience, producing coilovers, suspension braces, differentials, roll cages, and chassis reinforcement components for top sport compact and all-wheel-drive platforms. Cusco parts are built to motorsport tolerances and are used by professional race teams competing in Japanese domestic market racing series alongside street performance enthusiasts worldwide.Popular UpgradesCusco coilover kits, strut tower braces, and rear member braces are the most popular products for Subaru WRX and STI, Toyota 86 and GR86, Mazda Miata, Honda Civic, and Mitsubishi Evo platforms. Cusco limited-slip differentials and differential braces provide improved traction and reduced chassis flex for track and autocross builds on AWD platforms. Cusco adjustable control arms and camber kits allow precise alignment correction after lowering springs or coilovers are installed.What chassis bracing does Cusco make for the Subaru WRX...
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