Splined repair sleeve for the input shaft of the transfer case AISIN WARNER TF-80SC TF-81SC - 47 splines (outer Ø 48 mm, inner Ø 40 mm, height 22 mm)

• Overall height - 21.85 mm;
• Number of splines - 47 pcs.;
• Outer diameter of splined part - 48 mm;
• Inner diameter - 40 mm;

In our practice of repairing and fitting automatic transmissions and transfer cases, we often encounter problems with wear or breakage of splined connections, both in transmissions and in transfer cases, power take-off shafts (PTO - Power Take Off), angular gearboxes and other variations of transfer cases.

The reasons can be very different:

• Riding style.
  Aggressive driving, abrupt starts, and off-road driving. Increased loads cause premature wear of the engine components.
  
• Overheat.
  Excessive load increases friction between components, heating them up. Elevated temperatures affect the physical properties of metals, leading to potential deformation and the formation of gaps, which ultimately leads to premature wear of joints and components.
  
• Scheduled maintenance (TO).
  Failure to comply with maintenance regulations leads to wear of dust- and moisture-proof components that prevent environmental influences on the protected components.
  If a worn or damaged oil seal or boot is not detected in a timely manner, dust and moisture can directly penetrate into the splined joints, causing corrosion that leads to metal degradation and its gradual destruction.

How does a car behave when the transfer case splines are worn out?

It all depends on the degree of wear of the splined coupling:

• Spline wear less than 15%.
  
  In the initial stages, while the gap between the splines remains within acceptable values, no significant changes in the vehicle's performance dynamics are observed.
  
• Spline wear is 30-45%.
  
  Significant wear of the splined connection prevents the connection from forming a firm grip, resulting in free play (play at the connection). The vehicle loses performance, and jolts and shocks are felt when engaging all-wheel drive.
  
• Spline wear is more than 60%.
  
  Critical wear and clearance between the splines, risk of breakage of the remaining splines. When the splined clutch rotates, torque transmission to the all-wheel drive differential is interrupted. All-wheel drive is impossible.
  
  In TF-80SC TF-81SC transmissions, splines wear out more often on the transfer case input shaft than on the differential. The connection between the transfer case input shaft and the differential is achieved through a splined coupling (2712-XC90D5RH FEBEST).

  

The connection point with the shaft is located on the outer part of the transmission and is more exposed to the external environment and, as a result, corrosion.

Recovery process:

1. A shaft with damaged splines is fixed in a lathe.
2. The damaged splines are cut off, and a seat is formed for a new splined sleeve.
3. A splined bushing made of hardened steel is pressed onto the shaft.
4. After pressing, the bushing is laser welded.
5. We receive a transfer case shaft with restored splines.