2011/05/16 Caterpillar

Pumper:

SPF343C (S/N: RTX1-UP)

Petroleum Transmission:

TH48-E80 (S/N: FRT1-UP)

Service Magazine SEPD1243, 21 February 2011, "Improved Software is Now Used for the TH48-E80 Petroleum Transmissions". Disregard this article. See the article that follows.

Description of Change: Improved software is now used on the TH48-E80 Petroleum Transmissions and the SPF343C Pumpers. The new 364-7208 Software Group inhibits skip shifts. If the selected gear is more than one step away than the current gear, the software will sequentially shift the transmission through the gear ranges until the selected gear is reached.

The new software also provides a torque limiting feature when in converter drive. This feature will limit engine speed when the lockup clutch is disengaged in order to limit the maximum torque in the transmission. The maximum allowed engine speed is calculated based on the torque converter output speed. When the torque converter output speed is zero, engine speed will be limited to approximately 1500 rpm. Limiting the rpm's will prevent shifting at high torque levels. Shifting at high torque levels can force clutches to absorb unusually high amounts of shift energy.

Adaptable To: The new 364-7208 Software Group is effective with the following Petroleum Transmissions and Pumpers:

• TH48-E80 (S/N: FRT522-UP)

• SPF343C (S/N: RTX447-UP)

The new 364-7208 Software Group is adaptable to the following Petroleum Transmissions and Pumpers:

• TH48-E80 (S/N: FRT1-521)

• SPF343C (S/N: RTX1-446)