FAW J6P Second Axis: Deconstructing 14 Critical Parts for Flawless Gear Output

Welcome to this critical deconstruction of the FAW J6P Second Axis, also known as the mainshaft, for the CA10TA160M gearbox in the FAW Jiefang CA3250P66K2L1T1E 6×4 dump truck. This technical guide analyzes the 14 components that make up the complete FAW J6P Second Axis assembly, which is the heart of the transmission’s “output” logic.

The FAW J6P Second Axis is the output shaft of the main 5-speed gear case. Its logic is to hold all the “driven” gears (1st-4th, Reverse) and the synchronizer sleeves that lock them. The integrity of this one shaft and its components is directly responsible for every gear shift and all power delivery to the wheels.

Core 1: The “Shaft & Gear Set” Logic (The FAW J6P Second Axis)

This group represents the “spine” and the “driven gears” of the main gearbox. The FAW J6P Second Axis is the component that the driver is “connecting” to when they select a gear.

1. Component: ‘Second axis’ (1701301-A7G)
This (Comp 1) is the ‘Second axis’ itself, the mainshaft. This is a long, heavy-duty shaft, precision-machined from hardened steel with multiple steps and grooves. Its logic is to act as the central “spine” for all the main driven gears.

The Alignment Logic is critical. The front “tip” of this FAW J6P Second Axis is supported by the pilot bushing *inside* the ‘First Axis’ (input shaft). The rear of the shaft is supported by a large bearing in the back of the gearbox case. This two-point support keeps it perfectly concentric.

The Gear Carrier Logic is its main function. The “steps” on the shaft are smooth, hardened surfaces on which all the free-spinning gears (Comp 5, 10, 12, 13, 14) ride, usually on needle bearings. The “splined” sections are where the ‘Sliding gear sleeves’ (Comp 8) are mounted, which are the parts that lock the gears to the FAW J6P Second Axis.

2. The Driven Gears (Comp 5, 10, 12, 13, 14)
This group includes: ‘Reverse gear’ (Comp 5), ‘First gear’ (Comp 10), ‘Second gear’ (Comp 12), ‘Third gear’ (Comp 13), and ‘Fourth gear’ (Comp 14).

The Freewheeling Logic is the key concept. All five of these “driven gears” are in *constant mesh* with their respective drive gears on the countershaft. However, they are *not* fixed to the FAW J6P Second Axis. They all spin freely on the shaft at different speeds.

When the driver selects “3rd gear,” they are *not* moving the gear itself. They are moving a ‘Sliding gear sleeve’ (Comp 8) to “lock” the ‘Third gear’ (Comp 13) to the FAW J6P Second Axis. At that moment, power flows from the countershaft, through the now-locked Comp 13, and out through the FAW J6P Second Axis.

Core 2: The “Engagement” Logic (Sleeves & Keys)

This group contains the components that perform the physical “locking” of the gears to the FAW J6P Second Axis. This is the core of the synchronizer assembly.

1. Component: ‘Sliding gear sleeve’ (1701316-A7G) – Qty 3
This (Comp 8) is the ‘Sliding gear sleeve’. There are three of them, likely for the 1-2 shift, the 3-4 shift, and the Reverse shift. This is the component that the driver’s shift fork physically slides back and forth on the splines of the FAW J6P Second Axis.

The Locking Logic is its function. The ‘sleeve’ has internal splines that match the FAW J6P Second Axis. When the driver shifts, this sleeve slides over a set of external “dog teeth” on the side of the target gear (e.g., ‘First gear’, Comp 10). This creates a solid, positive, non-slip lock, making the gear and the shaft spin as one unit.

2. The “Detent Key” Group (Comp 3, 4)
This group includes: ‘Three-sided key’ (Comp 3) and ‘Snap ring – three-sided key’ (Comp 4). This is the “synchronizer key” or “strut.”

The Detent Logic is the function of the ‘Three-sided key’ (Comp 3). This small key sits in a groove in the synchronizer hub (which is splined to the FAW J6P Second Axis) and is pushed outwards by a spring (not listed) into a groove *inside* the ‘Sliding gear sleeve’ (Comp 8).

This key is what creates the “neutral” position for the sleeve. It provides the “snap” and “click” feeling in the gear lever. The ‘Snap ring’ (Comp 4) is a small retainer that holds this key in its slot, preventing it from falling out during assembly or operation.

Core 3: The “Positioning & Spacer” Logic (Washers)

This final group of components is arguably the most critical for a long-lasting, quiet FAW J6P Second Axis. Their logic is to precisely control the “end play” and spacing of all the spinning gears.

1. The “Reverse Gear” Spacer Group (Comp 6, 7)
This group includes: ‘Positioning washer – reverse gear’ (Comp 6) and ‘Limiting washer – reverse gear’ (Comp 7). These are the dedicated spacers for the ‘Reverse gear’ (Comp 5).

The Thrust Logic is their function. The ‘Positioning washer’ (Comp 6) likely sits behind the gear, setting its base position on the FAW J6P Second Axis. The ‘Limiting washer’ (Comp 7) sits on the other side. Together, these washers create a “sandwich” that controls the gear’s “axial play” (fore-and-aft movement). This precise spacing is essential for proper engagement with the reverse idler gear and the synchronizer sleeve.

2. The “Main Gear” Spacer Group (Comp 9, 11)
This group includes: ‘Limiting washer – gear’ (Comp 9, Qty 4) and ‘Inter-shaft limiting washer’ (Comp 11, Qty 2).

The Spacer Logic is the job of the ‘Limiting washers’ (Comp 9). These four washers are the “spacers” that sit on the FAW J6P Second Axis *between* the free-spinning gears (e.g., between 1st and 2nd, 2nd and 3rd, etc.). They prevent the hardened gears from rubbing directly against each other, which would generate immense heat and destructive metal particles.

The Thrust Bearing Logic is the job of the ‘Inter-shaft limiting washers’ (Comp 11). These are likely the main “thrust washers” for the entire gear set, located at the front and back of the gear stack. They absorb the massive axial forces generated by the helical-cut gears, protecting the FAW J6P Second Axis bearings from being destroyed.

3. Component: ‘Spring cylindrical pin’ (Q5280310)
This (Comp 2) is a ‘Spring cylindrical pin’, also known as a “roll pin.” Its Locking Logic is to act as a secure, vibration-proof fastener. It is likely used to lock the main shift rail (which moves the forks) in place, or to secure a synchronizer hub (which holds Comp 3) to the FAW J6P Second Axis, preventing it from rotating or sliding.

FAW J6P Second Axis: Complete 14-Part Breakdown

The following table provides the complete, detailed breakdown of all 14 component types in the FAW J6P Second Axis assembly for the FAW Jiefang CA3250P66K2L1T1E 6×4 dump truck.

Core Specifications

The specifications for the FAW J6P Second Axis are defined by its function as the central output shaft for the main gearbox, holding the primary set of “driven” gears.