Allison B 400 - Comparing Recorded Data to Specifications

Copyright © 1998 General Motors Corp. B–3
WTEC II ELECTRONIC CONTROLS TROUBLESHOOTING MANUAL
APPENDIX B — CHECKING CLUTCH PRESSURES
C. Comparing Recorded Data to Specifications
1. Be sure that engine speed and transmission sump fluid temperatures were within the values
specified in Table B–1.
2. Compare the main pressure and clutch pressure data, recorded in Step B, with the specifications in
Table B–2.
3. If clutch pressures are within specifications, return the transmission and vehicle to their original
configuration and proceed with electrical troubleshooting.
4. If clutch pressures are not within specification, take corrective action to replace the internal parts
of the transmission necessary to correct the problem. (Refer to the Transmission Service Manual
for the model being checked.)
5. Recheck pressure values after the transmission has been repaired.
6. Return the transmission to its original configuration. (Remove instrumentation and reinstall any
components removed for the pressure testing.)
MD 3070 — High
Speed
2080–2120 Reverse C3 C5
Neutral C5
LoC C3 C6
1C C1 C5
2C C1 C4
2L C1 C4 LU
3L C1 C3 LU
4L C1 C2 LU
5L C2 C3 LU
6L C2 C4 LU
HD/B 500 — High
Speed
1780–1820 Reverse C3 C5
Neutral C5
1C C1 C5
2C C1 C4
2L C1 C4 LU
3L C1 C3 LU
4L C1 C2 LU
5L C2 C3 LU
6L C2 C4 LU
Table B–1. Clutch Pressure Test Conditions (cont’d)
Transmission Model/Test
Type
Engine
rpm
Sump Fluid Temp Range Clutches Pressurized