| Size: | |
|---|---|
| Quantity: | |
| Parameter | Specification |
|---|---|
| Function | Enables smooth gear engagement between 3rd and 4th gears in manual transmissions by synchronizing shaft and gear speeds |
| Transmission Model | Compatible with FAST 12JSDX240T manual 12-speed gearbox |
| Gearbox Input Torque | Up to 2400 N·m |
| Gear Ratios (Relevant Gears) | - 3rd Gear Ratio: 8.22 - 4th Gear Ratio: 6.52 |
| Transmission Oil Capacity | 16 liters (for full system fill) |
| Material | High-strength alloy steel (heat-treated for wear and impact resistance) |
| Assembly Type | Complete synchronizer assembly including synchronizer hub, sleeve, blocking rings (synchronizer rings), keys, springs, and sliders |
| Net Weight (Approx.) | ~5.5 kg |
| Gross Weight (Packaged) | ~6.0 kg |
| Package Dimensions | Approx. 20 cm × 20 cm × 10 cm per unit |
| Packaging Type | Neutral carton box; OEM/custom packaging available (with logo, branding, etc.) |
| Minimum Order Quantity (MOQ) | Typically 2 pieces Bulk orders (≥100 pcs): eligible for wholesale pricing |
| Quality Status | Brand new, original equipment (OE) standard |
| Warranty Period | Standard industry warranty: 6 months |
 |  | |
| Brand | Compatible Models |
|---|---|
| Shaanxi Auto (SX / Shacman) | - Delong F3000 - F2000 - X3000 (Most post-2009 heavy-haul variants) |
| Sinotruk (CNHTC) | - HOWO A7 - Huanghe Tongshuai (Yellow River Commander) (Models configured with FAST 12JSDX240T transmission) |
| FAW Jiefang | Selected heavy-duty models fitted with FAST 12-speed gearbox |
| Foton Auman (Ordinary GTL) | - Auman GTL 470 HP and similar high-torque versions using this transmission |
Commonly deployed in:
Long-haul logistics
Mining and quarry transport
Bulk cargo hauling
Heavy construction and infrastructure projects
Specifically engineered for 3rd and 4th gear synchronization.
Quickly matches rotational speed between mainshaft and countershaft gears.
Eliminates gear clash and grinding during shifting.
Ensures silent, jerk-free gear changes, even under load.
Built to handle extreme torque (up to 2400 N·m) during:
Heavy-load startup
Hill climbing
Rough terrain operation
High-strength steel construction ensures excellent:
Wear resistance
Fatigue strength
Dimensional stability under stress
Optimized design minimizes internal friction during synchronization.
Maintains near-zero power loss — contributes to overall drivetrain efficiency.
Helps reduce fuel consumption over long operating cycles.
Suitable for continuous use in:
Dusty environments
High-vibration conditions
Frequent stop-start or slope-heavy routes
Resists deformation and fatigue over extended service life.
| Category | Information |
|---|---|
| Universal Cross Numbers | ❌ No officially published universal cross-reference numbers (e.g., WVA, ATA, or global aftermarket codes) |
| Reason | This is a model-specific OE component for the FAST 12JSDX240T transmission |
| Recommended Replacement Method | Always use original OE number: 12JSDX240T-1701180 when ordering or replacing |
| Compatibility Risk Warning | Avoid using unverified substitutes — mismatched synchronizers may cause: |
Poor synchronization
Premature wear
Gear lock-up or failure |
During full transmission overhauls, this synchronizer is often replaced alongside other gear-specific units:
| Gear Range | Part Number | Description |
|---|---|---|
| 1st/2nd Gear | 12JSDX240T-1701170 | 1st/2nd Gear Synchronizer Assembly |
| 3rd/4th Gear | 12JSDX240T-1701180 | ← This Part |
| 5th/6th Gear | 12JSDX240T-1701190 | 5th/6th Gear Synchronizer Assembly |
| Application | Details |
|---|---|
| Long-Distance Freight Transport | Frequent gear shifts require reliable synchronization for driver comfort and reduced mechanical wear |
| Mining & Quarry Operations | Constant heavy loading and rough terrain demand robust transmission components |
| Construction Logistics | Stop-and-go traffic combined with steep grades increases synchronizer workload |
| Cold Climate Regions | Proper lubrication and warm-up procedures essential to prevent cold-shift shock |
| High-Altitude Routes | Requires precise shift timing due to engine power drop — smooth sync improves control |
Inspect Before Installation
Synchronizer ring (blocking ring) for wear, chipping, or "glazing"
Hub teeth for damage
Spring tension and key positioning
Check all components:
Replace any worn or damaged sub-components before reassembly.
Install with Correct Torque & Alignment
Ensure proper clearance and alignment when mounting into the main shaft.
Use manufacturer-recommended tools and fixtures if available.
Do not force installation — misalignment causes binding and uneven wear.
Use Only Approved Transmission Oil
Must comply with FAST 12JSDX240T specifications
Recommended oil type: GL-5 85W/90 or 80W/90 synthetic gear oil
Change interval: Every 40,000–60,000 km or as per vehicle manual
Clean oil passages before refill — sludge and metal particles accelerate synchronizer wear
Avoid Improper Driving Habits
Synchronizer ring cracking
Key breakage
Permanent gear engagement issues
❌ Never perform “floating gears” or coasting in neutral on downhill slopes
❌ Do not force shifts under load without full clutch disengagement
❌ Avoid rapid sequential shifting without proper pedal coordination
➤ These behaviors create excessive heat and stress, leading to:
Monitor for Early Failure Signs
Replace immediately if you observe:
Difficulty engaging 3rd or 4th gear
Grinding noise during shifting
Gear slipping or popping out under load
Increased shift effort
Handle with Care During Storage & Transport
Keep in dry, clean environment
Prevent rust on machined surfaces
Avoid dropping or impact — precision components can be internally damaged
Only Replace in Clean Workshop Environment
Perform transmission work in dust-free areas
Protect open gearbox from contamination
Use lint-free cloths and clean tools
