Torque Converter Stall Test Notes
Forum Thread 1
Have you done a stall test? Make sure ATF is correct at cold temp.
A Stall test is used to confirm transmission and torque converter problems by placing the maximum load on the transmission and torque converter.
I don’t know what the stall speed is for the Patrol so here is a little way to find out.
Drive the Patrol at low speed in 2nd and then go full throttle. The RPM level that the engine immediately accelerates to is the flash stall. Flash stall speed is one of the most useful ways to truly gauge the stall speed characteristics of a torque converter and how those characteristics will influence the acceleration potential of a vehicle.
Now that ATF and engine warm. Block all 4 wheels, apply full hand brake, left foot apply full brakes. Now start the engine and shift to 1. Start to press the throttle to full and make a note of the RPM. From moment of pressing the throttle to releasing it should only take 5 seconds. Put the auto lever in N and let the fluid flush the auto box, increase the RPM to 2000 to get the ATF fluid moving quickly. Then do the same for 2, D, R and once finished go to P. Record the RPM for each gear and post it here if you like for the people to discuss.
Excessive engine speed during a stall test indicates slipping clutches in the transmission.
Have you done a stall test? Make sure ATF is correct at cold temp.
A Stall test is used to confirm transmission and torque converter problems by placing the maximum load on the transmission and torque converter.
I don’t know what the stall speed is for the Patrol so here is a little way to find out.
Drive the Patrol at low speed in 2nd and then go full throttle. The RPM level that the engine immediately accelerates to is the flash stall. Flash stall speed is one of the most useful ways to truly gauge the stall speed characteristics of a torque converter and how those characteristics will influence the acceleration potential of a vehicle.
Now that ATF and engine warm. Block all 4 wheels, apply full hand brake, left foot apply full brakes. Now start the engine and shift to 1. Start to press the throttle to full and make a note of the RPM. From moment of pressing the throttle to releasing it should only take 5 seconds. Put the auto lever in N and let the fluid flush the auto box, increase the RPM to 2000 to get the ATF fluid moving quickly. Then do the same for 2, D, R and once finished go to P. Record the RPM for each gear and post it here if you like for the people to discuss.
Excessive engine speed during a stall test indicates slipping clutches in the transmission.
Forum Thread 2
This test should be performed by a shop, but if you can locate the stall speed specification, you can do it yourself. Stall speed is when the engine rpm gets as high as the transmission will let it. The stall test checks converter one-way clutch operation and installation, the holding ability of the forward clutch, reverse clutch, the low and reverse bands, the planetary one-way clutch, and engine performance. Perform test with engine coolant and transmission fluid at operating temperature.
To perform a stall test, firmly apply service and parking brakes; with transmission in ranges D, 2, 1, and R, press the accelerator to the floor and hold it just long enough to let the engine reach full RPM.
NOTE: Do not hold throttle open for more than five seconds at a time or transmission damage may result.
After each range, move selector lever to N and run engine at 1,000 RPM for approximately 15 seconds to cool the converter before making the next test.
This test should be performed by a shop, but if you can locate the stall speed specification, you can do it yourself. Stall speed is when the engine rpm gets as high as the transmission will let it. The stall test checks converter one-way clutch operation and installation, the holding ability of the forward clutch, reverse clutch, the low and reverse bands, the planetary one-way clutch, and engine performance. Perform test with engine coolant and transmission fluid at operating temperature.
To perform a stall test, firmly apply service and parking brakes; with transmission in ranges D, 2, 1, and R, press the accelerator to the floor and hold it just long enough to let the engine reach full RPM.
NOTE: Do not hold throttle open for more than five seconds at a time or transmission damage may result.
After each range, move selector lever to N and run engine at 1,000 RPM for approximately 15 seconds to cool the converter before making the next test.
Workshop Manual
Stall Revolution
2,950 – 3,200 rpm (RE4R03A)
LOCK-UP SPEED SPECIFICATIONS - 300ZX TURBO
Full Throttle Half Throttle
Application MPH MPH
OD ON
Lock-Up ON in 4th ....... 114-119 ............ 114-119
Lock-Up OFF in 4th ...... 111-116 .............. 73-68
OD OFF
Lock-Up ON in 3rd ........ 75-80 ............... 55-60
Lock-Up OFF in 3rd ....... 68-73 ............... 46-51
SHIFT SPEED SPECIFICATIONS - 300ZX TURBO
Full Throttle Half Throttle
Application MPH MPH
1st-2nd ............... 42-45 .................... 29-32
2nd-3rd ............... 75-80 .................... 55-59
3rd-4th .............. 114-120 ................... 85-89
4th-3rd .............. 110-116 ................... 48-53
3rd-2nd ............... 68-73 .................... 17-21
2nd-1st ............... 21-23 ...................... 6-9
STALL SPEED SPECIFICATIONS
Application RPM
300ZX
Non-Turbo .................................... 2450-2650
Turbo ........................................ 2950-3250
STALL SPEED TEST RESULTS
* Stall Speed Low in All Positions
Insufficient engine performance or faulty torque converter one-way clutch.
* Stall Speed High in All Positions
Low and reverse brake slipping, faulty low one-way clutch or hydraulic circuit for line pressure control.
* Stall Speed High in "R" Position Only
Reverse clutch slipping or low and reverse brake slipping.
* Stall Speed High in "D", "2" and "R" Positions, Okay in "1" Position
Reverse clutch, forward clutch, forward one-way clutch or low one-way clutch.
* Stall Speed High in "D", "2" & "1" Positions, Okay in "R" Position
Forward clutch, overrun clutch or forward one-way clutch.
NOTE: Condition of high clutch and brake band cannot be confirmed by stall speed test.
2,950 – 3,200 rpm (RE4R03A)
LOCK-UP SPEED SPECIFICATIONS - 300ZX TURBO
Full Throttle Half Throttle
Application MPH MPH
OD ON
Lock-Up ON in 4th ....... 114-119 ............ 114-119
Lock-Up OFF in 4th ...... 111-116 .............. 73-68
OD OFF
Lock-Up ON in 3rd ........ 75-80 ............... 55-60
Lock-Up OFF in 3rd ....... 68-73 ............... 46-51
SHIFT SPEED SPECIFICATIONS - 300ZX TURBO
Full Throttle Half Throttle
Application MPH MPH
1st-2nd ............... 42-45 .................... 29-32
2nd-3rd ............... 75-80 .................... 55-59
3rd-4th .............. 114-120 ................... 85-89
4th-3rd .............. 110-116 ................... 48-53
3rd-2nd ............... 68-73 .................... 17-21
2nd-1st ............... 21-23 ...................... 6-9
STALL SPEED SPECIFICATIONS
Application RPM
300ZX
Non-Turbo .................................... 2450-2650
Turbo ........................................ 2950-3250
STALL SPEED TEST RESULTS
* Stall Speed Low in All Positions
Insufficient engine performance or faulty torque converter one-way clutch.
* Stall Speed High in All Positions
Low and reverse brake slipping, faulty low one-way clutch or hydraulic circuit for line pressure control.
* Stall Speed High in "R" Position Only
Reverse clutch slipping or low and reverse brake slipping.
* Stall Speed High in "D", "2" and "R" Positions, Okay in "1" Position
Reverse clutch, forward clutch, forward one-way clutch or low one-way clutch.
* Stall Speed High in "D", "2" & "1" Positions, Okay in "R" Position
Forward clutch, overrun clutch or forward one-way clutch.
NOTE: Condition of high clutch and brake band cannot be confirmed by stall speed test.
HYDRAULIC PRESSURE TESTS
LINE PRESSURE TEST PROCEDURE
1) Warm engine and transmission to normal operating temperature. Check engine and transmission fluid levels and add fluid as necessary. Install pressure gauge to line pressure port for "D", "2" and "1" positions.
2) Set parking brake and block wheels. Apply foot brake fully while line pressure test at stall speed is performed. Start engine and measure line pressure at idle and stall speed, in "D", "2", "1" and "R" positions. When measuring line pressure at stall speed, follow stall speed test procedure. Note pressure readings and refer to the LINE PRESSURE SPECIFICATIONS table.
LINE PRESSURE SPECIFICATIONS
Pressure
Application psi (kPa)
300ZX
At idle
"D", "2" & "1" positions ............. 61-67 (422-461)
"R" position ........................ 97-102 (667-706)
At stall speed
"D", "2" & "1" positions ......... 148-159 (1020-1098)
"R" position ..................... 206-218 (1422-1500)
1) Warm engine and transmission to normal operating temperature. Check engine and transmission fluid levels and add fluid as necessary. Install pressure gauge to line pressure port for "D", "2" and "1" positions.
2) Set parking brake and block wheels. Apply foot brake fully while line pressure test at stall speed is performed. Start engine and measure line pressure at idle and stall speed, in "D", "2", "1" and "R" positions. When measuring line pressure at stall speed, follow stall speed test procedure. Note pressure readings and refer to the LINE PRESSURE SPECIFICATIONS table.
LINE PRESSURE SPECIFICATIONS
Pressure
Application psi (kPa)
300ZX
At idle
"D", "2" & "1" positions ............. 61-67 (422-461)
"R" position ........................ 97-102 (667-706)
At stall speed
"D", "2" & "1" positions ......... 148-159 (1020-1098)
"R" position ..................... 206-218 (1422-1500)
LINE PRESSURE TEST RESULTS
* Line Pressure Low At Idle In All Positions:
Oil pump wear, control piston damage, pressure regulator valve or plug sticking, or fluid pressure leakage between oil strainer and pressure regulator.
* Line Pressure Low At Idle In A Particular Position:
Check for fluid pressure leakage between manual valve and the particular clutch.
* Line Pressure High At Idle:
Misadjusted throttle sensor, fluid temperature sensor or line pressure solenoid damaged, pressure modifier valve sticking or pressure regulator valve sticking.
* Line Pressure Low At Stall Speed:
Misadjusted throttle sensor, control piston damaged, line pressure solenoid sticking, pressure regulator valve or plug sticking, pressure modifier valve or pilot valve sticking.
* Line Pressure Low At Idle In All Positions:
Oil pump wear, control piston damage, pressure regulator valve or plug sticking, or fluid pressure leakage between oil strainer and pressure regulator.
* Line Pressure Low At Idle In A Particular Position:
Check for fluid pressure leakage between manual valve and the particular clutch.
* Line Pressure High At Idle:
Misadjusted throttle sensor, fluid temperature sensor or line pressure solenoid damaged, pressure modifier valve sticking or pressure regulator valve sticking.
* Line Pressure Low At Stall Speed:
Misadjusted throttle sensor, control piston damaged, line pressure solenoid sticking, pressure regulator valve or plug sticking, pressure modifier valve or pilot valve sticking.
