Procedures for Verification of TH48-E80 Petroleum Transmission (Frac) Transmission Controls{3166, 3167} Caterpillar

Petroleum Transmission:

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

Introduction

The TH48-E80 transmission controls maybe configured with two different rotary selector spools. These spools enable the transmission to either operate with eight forward gear ranges or seven forward gears ranges and warm-up gear. Customer preference generally determines what spool is installed. Occurrences of spool change outs are common, the transmission arrangement may not always define transmission hardware. This special instruction contains the procedure for verification of the TH48-E80frac transmission controls. Special instruction, REHS3520 contains the procedure to change the rotary selector spool.

Safety

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Improper operation, lubrication, maintenance or repair of this product can be dangerous and could result in injury or death. Do not operate or perform any lubrication, maintenance or repair on this product, until you have read and understood the operation, lubrication, maintenance and repair information.

Required Tools

• Cat Electronic Technician and Communications Adapter

• 9/16 inch Allen wrench or socket (male hex)

• 1/4 inch Extension 6 inches long and ratchet or breaker bar.

Procedure for Verification

1. Start the engine and allow transmission oil temperature to warm up to more than 40° C (104° F).

2. Shift transmission to neutral.

3. Shut down engine.

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Illustration 1	g03660821
(1) Down-shift solenoid (2) Up-shift solenoid (3) Plug (4) Lockup valve

4. Disconnect the transmission harness from down-shift (1) and up-shift (2) solenoids.

5. Remove plug (3). A 9/16 inch allen wrench or socket is required.

   Note: Replace O-ring with 238-5082 O-ring if damaged.

6. Insert 1/4 inch extension through the case and engage the extension into end of rotary selector spool.

   Note: Rotation of rotary selector spool will cause transmission to shift gears. Rotation of output shaft will occur.

   Note: Do not attempt to rotate manually Rotary selector spool with shift solenoids connected to transmission harness. Damage or Injury may occur.

7. With the engine not running, manually rotate Rotary Selector Spool counter clockwise until you are comfortable with the normal amount of torque required to rotate from detent to detent. Each detent position represents one gear shift.

8. Ensure that rotary selector spool is rotated fully clockwise until resting against the hard stop, this position is the first position, NEUTRAL gear.

   Note: All rotation instructions, are as viewed looking at the removed plug hole on the left side of the transmission.

9. Start the engine and allow to idle.

10. Connect Cat ET and use the status screens to view the transmission output shaft speed. Record the transmission output shaft speed: __________rpm.

11. Rotate the rotary selector spool one position counter clockwise, this position is the second position, Park Gear. Record the transmission output shaft speed ________ rpm. The transmission output shaft speed should be zero and the transmission should be in Park Gear.

12. Rotate the Rotary Selector Spool one position counter clockwise, this position is the third position. Record the transmission output shaft speed: _____ rpm. Record the torque converter output shaft speed: _____ rpm.

    If the transmission output shaft speed is ZERO rpm and the torque converter output shaft speed is ZERO rpm, then the transmission is in Stall Gear, has a stall mode spool installed, and needs to have the transmission software configuration set to 18001 (ICM Lockup Valve (4) ) or 18002 (ECPC Lockup Valve (4) ) per Special Instruction, REHS4541.

    If the transmission output shaft speed is NOT ZERO rpm and the torque converter output shaft speed is NOT ZERO rpm, then the transmission is in gear. Divide the torque converter output speed by the transmission output speed and record the result: ________. Compare the result to the following table to determine the gear that the transmission is in.

    Torque Converter Output Speed / Transmission Output Speed = _________.

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    Table 1

    TH48-E80 Planetary Gear Ratio
    Gear	Gear Ratio
    Neutral Gear
    Park Gear	0.00
    Warm-up Gear	0.00
    First Gear	4.54
    Second Gear	3.33
    Third Gear	2.99
    Fourth Gear	2.46
    Fifth Gear	2.20
    Sixth Gear	1.85
    Seventh Gear	1.62
    Eighth Gear	1.36

    If the gear ratio indicates that the transmission is in First Gear, then it has a standard spool installed, and needs to have the transmission software configuration set to 18000 (ICM Lockup Valve (4) ) or 18004 (ECPC Lockup Valve (4) ) per Special Instruction, REHS4541.

    Note: Step 12 can be repeated for each spool position. Gear shifts will be consecutive. See the following table.

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    Table 2

    TH48-E80 Gear Sequence
    TH48-E80 Gear Sequence Spool Position	Warm-up (7 speed) Application Code 18001 or 18002	Standard (8 speed) Application Code 18000 or 18004
    1	Neutral Gear	Neutral Gear
    2	Park Gear	Park Gear
    3	Warm-up Gear	First Gear
    4	First Gear	Second Gear
    5	Second Gear	Third Gear
    6	Third Gear	Fourth Gear
    7	Fourth Gear	Fifth Gear
    8	Fifth Gear	Sixth Gear
    9	Sixth Gear	Seventh Gear
    10	Seventh Gear	Eighth Gear

13. When completed, rotate the rotary selector spool clockwise until hitting the stop and is in Neutral Gear.

14. Remove all tooling, install the controls plug, and reconnect the transmission harness.

15. Configure the transmission software as per the test results.

16. Clear any codes generated due to the shift solenoids being disconnects.

17. Test the shifting functionality of the transmission.

Procedure for Verification of Lockup Clutch Valve

The Lockup Clutch Valve type must be identified on the TH48-E80 Petroleum Transmission in order to ensure proper software configuration. Improper configuration can lead to slow lock up clutch engagement or valve solenoid failure.

The Lockup Clutch valve is located on the torque converter housing and the right-hand side of the transmission as viewed from the rear. As shown in Illustration 1.

Illustration 2	g03660963
367-9108 Lockup Clutch Valve and Mounting Gp (ECPC)

Illustration 3	g03660979
261-3050 Lockup Clutch and Synchronizing Valve (ICM)

Use figures to determine if the transmission is equipped with an ICM or ECPC valve group. Once the lockup clutch valve and shift selector spool are identified, use Cat ET to set transmission software configuration per Special Instruction, REHS4541.