Hydraulic System
HYDRAULIC SYSTEM SYMPTOM CHART
| SYMPTOM | Check these items on the PROBABLE CAUSE List | Check these items on the NOTES List | |
|---|---|---|---|
| Engine runs, but vehicle does not move in any gear. | 1, 2, 3, 5, 6. 7, 36, 38 | K, L, R. S | |
| Vehicle moves in [2], [R], but not in [D3 ], [D4 ], position. | 6,8,9,10,30,54 | C, M, O | |
| Vehicle moves in [D3 ], [D4 ], [R], but not in [2] position. | 6,11,12,24 | C, L | |
| Vehicle moves in [D3 ], [D4 ], [2], but not in [R] position. | 4, 6, 14, 15, 31 | C, L, Q | |
| Vehicle moves in [N] position. | 10, 12, 13, 14, 16, 29, 33, 34, 35 | C, D | |
| Excessive idle vibration | 1,2,19, 32,36, 45, 47, 48,52 | B, K, L | |
| Poor acceleration; flares on starting off in [D4 ], [D3 ] position | |||
| Stall rpm high in [D3 ], [D4 ], [2] position | 1,2,3,6,38,41 | K, L, R | |
| Stall rpm high in [D3 ], [D4 ] position | 6,8,10 | C, D | |
| Stall rpm high in [2] position | 6,12 | C, D | |
| Stall rpm is in specification | 14 | N | |
| Stall rpm low | 17, 18, 32, 45, 47, 48, 52 | R | |
| No shift | 19, 20, 40, 48, 49, 52 | G, L | |
| Fails to shift in [D3 ], [D4 ] position; from 1st to 3rd gear | 22, 49, 52 | ||
| Fails to shift in [D3 ], [D4 ] position; from 1st to 4th gear | 22,23, 48, 52 | ||
| Erratic upshifting | |||
| 1-2 upshift, 2-3 upshift, 3-4 upshift | 18, 52, 59 | ||
| 1-2 upshift | 21,48,52 | ||
| 2-3 upshift | 22, 49, 52 | ||
| 3-4 upshift | 23, 48, 52 | ||
| Harsh upshift (1-2) | 12, 19, 20, 29, 50, 51, 52, 58, 59 | C, D, E | |
| Harsh upshift (2-3) | 13, 19, 20, 24, 27, 29, 50, 51, 52, 58, 59 | C, D, E, H, L | |
| Harsh upshift (3-4) | 14, 19, 20, 25, 28, 29, 50, 51, 52, 58, 59 | C, D, E, I, L | |
| Harsh downshift (2-1) | 19, 20, 24, 43, 52, 55, 58, 59 | O | |
| Harsh downshift (3-2) | 12, 19, 20, 25, 43, 52, 56, 58, 59 | C, D, E, H | |
| Harsh downshift (4-3) | 13, 19, 20, 26, 43, 52, 57, 58, 59 | C, D, E, I | |
| Flares on 2-3 upshift | 13, 19, 20, 24, 27, 51, 52 | E, L | |
| Flares on 3-4 upshift | 14, 19, 20, 25, 28, 51, 52 | E, L, N | |
| Excessive shock on 2-3 upshift | 13, 19, 20, 24, 27, 43, 50, 51, 52, 58, 59 | E, L, N | |
| Excessive shock on 3-4 upshift | 14, 19, 20, 25, 28, 43, 50, 51, 52, 58, 59 | E, L, N | |
| Late shift from [N] position to [D4 ] or [D3 ] position | 10,30 | M | |
| Late shift from [N] position to [R] position | 4, 14, 21, 53 | Q | |
| Noise from transmission in all shift lever positions | 2, 37 | K, L, Q | |
| Vehicle does not accelerate more than 31 mph (50 km/h). | 17 | ||
| Shift lever does not operate smoothly. | 6, 39 | P | |
| Fails to shift; stuck in 4th gear | 48, 49, 52 | ||
| Transmission will not shift into parking gear in [P] position. | 6,39 | P | |
| Stall rpm high; all clutch pressures are in specification. | 41 | D, K, O | |
| Lock-up clutch does not disengage. | 19, 44, 45, 46, 47, 50, 51, 52, 59 | E, L | |
| Lock-up clutch does not operate smoothly. | 19, 41, 44, 45, 46, 47, 50, 51, 52, 59 | L | |
| Lock-up clutch does not engage. | 19, 41, 44, 45, 46, 47, 50, 51, 52,59 | E, L | |
| Vibration in all positions | 36 | ||
HYDRAULIC SYSTEM SYMPTOM CHART
| PROBABLE CAUSE | |||
|---|---|---|---|
| 1 | Low ATF | 41 | Torque converter check valve stuck |
| 2 | ATF pump worn or binding | 42 | Foreign material in separator plate |
| 3 | Regulator valve stuck | 43 | CPB valve stuck |
| 4 | Servo valve stuck | 44 | Lock-up timing valve stuck |
| 5 | Mainshaft worn/damaged | 45 | Lock-up shift valve stuck |
| 6 | Shift cable broken/out of adjustment | 46 | Lock-up control valve stuck |
| 7 | Final gears worn/damaged | 47 | Lock-up piston defective |
| 8 | One-way (sprag) clutch worn/damaged | 48 | Shift control solenoid valve A defective |
| 9 | 1st gears worn/damaged (2 gears) | 49 | Shift control solenoid valve B defective |
| 10 | 1st clutch defective | 50 | Lock-up control solenoid valve A defective |
| 11 | 2nd gears worn/damaged (2 gears) | 51 | Lock-up control solenoid valve B defective |
| 12 | 2nd clutch defective | 52 | PCM defective |
| 13 | 3rd clutch defective | 53 | Servo control valve stuck |
| 14 | 4th clutch defective | 54 | 1st accumulator defective |
| 15 | Reverse gears worn/damaged (3 gears) | 55 | Foreign material in 2nd exhaust office |
| 16 | Excessive ATF | 56 | Foreign material in 3rd exhaust office |
| 17 | Torque converter one-way clutch defective | 57 | Foreign material in 4th exhaust office |
| 18 | Engine throttle cable out of adjustment | 58 | Mainshaft speed sensor defective |
| 19 | Linear solenoid assembly defective | 59 | Countershaft speed sensor defective |
| 20 | CPC valve stuck | ||
| 21 | 1-2 shift valve stuck | ||
| 22 | 2-3 shift valve stuck | ||
| 23 | 3-4 shift valve stuck | ||
| 24 | 2nd accumulator defective | ||
| 25 | 3rd accumulator defective | ||
| 26 | 4th accumulator defective | ||
| 27 | 2nd office control valve stuck | ||
| 28 | 3-4 office control valve stuck | ||
| 29 | Foreign material in main office | ||
| 30 | Foreign material in 1st office | ||
| 31 | Foreign material in reverse office | ||
| 32 | Engine output low | ||
| 33 | Needle bearing worn/damaged | ||
| 34 | Thrust washer worn/damaged | ||
| 35 | Clutch clearance incorrect | ||
| 36 | Drive plate defective or transmission misassembly | ||
| 37 | Torque converter housing or transmission housing bearing worn/damaged | ||
| 38 | ATF strainer clogged | ||
| 39 | Joint in shift cable and transmission or body worn | ||
| 40 | Modulator valve stuck | ||
HYDRAULIC SYSTEM SYMPTOM CHART
| The following symptoms can be caused by improper repair or assembly | Check these items on the PROBABLE CAUSE DUE TO IMPROPER REPAIR List | Items on the NOTES List |
|---|---|---|
| Vehicle creeps in [N] position. | R1, R2 | |
| Vehicle does not move in [D3 ] or [D4 ] position. | R4 | |
| Transmission locks up in [R] position. | R3, R11 | |
| Excessive drag in transmission | R6 | K, R |
| Excessive vibration, rpm related | R7 | |
| Noise with wheels moving only | R5 | |
| Main seal pops out. | R8 | S |
| Various shifting problems | R9, R10 |
HYDRAULIC SYSTEM SYMPTOM CHART
| PROBABLE CAUSE DUE TO IMPROPER REPAIR | |
|---|---|
| R1 | Improper clutch clearance |
| R2 | Improper gear clearance |
| R3 | Parking brake lever installed upside down. |
| R4 | One-way (sprag) clutch installed upside down. |
| R5 | Reverse selector hub installed upside down. |
| R6 | ATF pump binding |
| R7 | Torque converter not fully seated in ATF pump. |
| R8 | Main seal improperly installed. |
| R9 | Springs improperly installed. |
| R10 | Valves improperly installed. |
| R11 | Shift fork bolt not installed. |
HYDRAULIC SYSTEM SYMPTOM CHART
| NOTES | |
|---|---|
| A | See flushing procedure, COOLER FLUSHING . |
| B | Set idle rpm in gear to specified idle speed. If still no good, adjust the motor mounts as outlined in INSTALLATION . |
| C | If the large clutch piston O-ring is broken, inspect the piston groove for rough machining. |
| D | If the clutch pack is seized or is excessively worn, inspect the other clutches for wear, and check the office control valves, CPC valve, and linear solenoid for free movement. |
| E | If the linear solenoid is stuck, inspect the clutches for wear. |
| G | If the 1-2 shift valve is stuck closed, the transmission will not upshift. If stuck open, the transmission has no 1st gear. |
| H | If the 2nd office control valve is stuck, inspect the 2nd and 3rd clutch packs for wear. |
| I | If the 3-4 office control valve is stuck, inspect the 3rd and 4th clutch packs for wear. |
| J | If the clutch pressure control valve is stuck closed, the transmission will not shift out of 1st gear. |
| K | Improper alignment of main valve body and torque converter housing may cause ATF pump seizure. The symptoms are mostly an rpm-related ticking noise or a high-pitched squeak. |
| L | If the ATF strainer is clogged with particles of steel or aluminum, inspect the ATF pump and differential pinion shaft. If both are OK and no cause for the contamination is found, replace the torque converter. |
| M | If the 1st clutch feed pipe guide in the right side cover is scored by the mainshaft, inspect the ball bearing for excessive movement in the transmission housing. If OK, replace the right side cover as it is dented. The O-ring under the guide is probably worn. |
| N |
|
| O | A worn or damaged sprag clutch is mostly a result of shifting the transmission in [D3 ] or [D4 ] position while the wheels rotate in reverse, such as rocking the vehicle in snow. |
| P | Inspect the frame for collision damage. |
| Q | Inspect for damage and wear:
Replace items 1,2,3 and 4 if worn or damaged. If the transmission makes a clicking, grinding, or whirring noise, also replace mainshaft 4th gear, reverse idler gear, and countershaft 4th gear. If the differential pinion shaft is worn, overhaul the differential assembly, replace ATF strainer, thoroughly clean the transmission and flush the torque converter, cooler, and lines. If bottom of 3rd clutch is swirled and transmission makes gear noise, replace the countershaft and final driven gear. |
| R | Be very careful not to damage the torque converter housing when replacing the main ball bearing. You may also damage the ATF pump when you torque down the main valve body. This will result in ATF pump seizure if not detected. Use the proper tools. |
| S | Install the main seal flush with the torque converter housing. If you push it into the torque converter housing until it bottoms out, it will block the fluid return passage and result in damage. |