po 746 and po840

[ultimate 02]

Hi, can any one help me with these codes? I have an 02 duramaxs with 120,000 miles,bully dog programmer. I run this in the highest setting plowing and pulling trailers,it been in limp in before because of the tranny slipping, i'm just wondering if this tranny is on the way out. Thanks a bunch,jason

[Jake99Z71]

Pressure Switch C Circuit P0840 This test compares the Pending failure occurs when S1 valve is destroked 125 ms A
Malfunction commanded valve position to C pressure switch indicates stroked for > 0.125 seconds. NOT Cold initialization unless transmissions fluid 25 ms
the pressure switch C feedback. (If a main pressure dropout is temperature > -25 deg. C.
(part of S1 valve integrity test) suspected or detected, then time limit increases Shutdown is NOT in process
to 0.125 seconds and 30 seconds, respectively.) Ignition voltage > 5 V and stable.
In response to the pending failure, S1 valve is retried by
triggering S1 valve command to stroked and
back to destroked. If the C pressure switch continues
to indicate stroked, then one of three malfunction
cases exists.
For Case 1 (electrical malfunction), Solenoid C Electrical
Malfunction (P0763) reports failure, also.
For Case 2 (mechanical malfunction), Pressure Switch
C Circuit Low/Stuck Closed (P0842) reports failure, also.
For Case 3 (intermittent malfunction), S1 valve retry
attempted 15 times and C pressure switch continues to
indicate stroked.

[Jake99Z71]

Solenoid "A" Controlled P0746 This test determines if the Pending failure occurs when accumulated No Output Speed Sensor DTCs (P0721, P0722) 2.25 s A
Clutch Stuck Off on-coming clutch energized by event timer >= 2 seconds. (For rough road conditions, No Input Speed_Sensor DTCs (P0716, P0717) 25 ms
Solenoid A engages during a use 2 seconds.) Timer accumulates No Reverse Pressure Switch DTCs (P0875, P0876)
forward range shift. when transmission is shifting, output speed >= Hydraulic System Pressurized
60 RPM, and commanded gear slip speed > 75 Output Speed >= 125 RPM
RPM. (For rough road conditions, use 150 RPM.) Turbine Speed >= 60 RPM
In response of pending failure, a Normal powertrain shutdown not in process
diagnostic response range is commanded. Normal or Cold powertrain initialization is complete
During this command, this test fails if Abs(Converter No Cold Mode operation
Slip) >= 230 RPM for > 10 samples. No abusive garage shift to 1st range detected
On-coming clutch control enabled
No range switch response active
Power downshift abort to previous range NOT active