- Wheel Loader:
- 966H (S/N: A6D1-UP; RYF1-UP; A6G1-UP; A6J1-UP; TAL1-UP)
- 972H (S/N: GTA1-UP; A7D1-UP; A7G1-UP; A7J1-UP)
Description of Change: Some reports have been received regarding noise from the hydraulic cylinders on these Wheel Loaders. The noise may be louder when the bucket is raised while heavily loaded. The noise is caused by friction interaction between the piston seal and the cylinder bore. The addition of a hydraulic oil additive will reduce hydraulic noise on these machines.
If noise is unacceptable on these machines, add 1 L (0.26 US gal) of 1U-9891 Hydraulic Oil Additive to the hydraulic tank. Slowly exercise the implements in order to distribute the additive through the hydraulic system. If 1 L (0.26 US gal) of additive does not eliminate the noise, a second 1 L (0.26 US gal) of additive may be added.
Adaptable To: The 1U-9891 Hydraulic Oil Additive may be added to any of the machines that are listed in the title block above.
The following machines did not have the 1U-9891 Hydraulic Oil Additive from the factory. These machines may need to have the hydraulic oil additive added to the hydraulic tank:
- 966H (S/N: A6D1836-2838; A6G3245-5688; A6J1059-1972)
- 972H (S/N: A7D707-1138; A7G1069-2218; A7J304-525)
- 966H (S/N: A6D1-1835,2839-UP; A6G1-3244,5689-UP; A6J1-1058,1973-UP; TAL1-UP; RYF1-UP)
- 972H (S/N: A7D1-706,1139-UP; A7G1-1068,2219-UP; A7J1-303,526-UP; GTA1-UP)