Think you know the 4l60? Then I need help.
07-17-2007, 05:31 PM
#1
Think you know the 4l60? Then I need help. I'm currently studying automatic transmissions at Southen Illinois and we are on the 4l60e right now. We have a scenarios worksheet that we are working on and I am stuck on a few questions and need some help.
The scenario that is giving me trouble is this....
Overhauled trans slipping in all gear ranges. Pressure tests show approx. 55lbs of pressure in all ranges and will not rise. Everything visually looks good and air checks with no problems. The trans works good when it's on a lift but slips when it's on the ground and slips very badly in reverse. Pressure control solenoid was removed and cleaned but not replaced. A remaned pump was installed but was not checked to see if it would slide. Pump output was checked by revving to 1500rmp and shutting the engine down but couldn't get the gauge to rise even if the engine was revved to 3500.
What components could cause low or no pressure rise?
How does "revving" the engine to 3000 rpm and shutting it off test the max output of the pump?
I would appreciate any ideas bc I'm kinda stuck on this problem and I really want to understand these transmissions... lol i'm kinda biased considering I have one and all.
The scenario that is giving me trouble is this....
Overhauled trans slipping in all gear ranges. Pressure tests show approx. 55lbs of pressure in all ranges and will not rise. Everything visually looks good and air checks with no problems. The trans works good when it's on a lift but slips when it's on the ground and slips very badly in reverse. Pressure control solenoid was removed and cleaned but not replaced. A remaned pump was installed but was not checked to see if it would slide. Pump output was checked by revving to 1500rmp and shutting the engine down but couldn't get the gauge to rise even if the engine was revved to 3500.
What components could cause low or no pressure rise?
How does "revving" the engine to 3000 rpm and shutting it off test the max output of the pump?
I would appreciate any ideas bc I'm kinda stuck on this problem and I really want to understand these transmissions... lol i'm kinda biased considering I have one and all.
07-17-2007, 05:59 PM
#2
Well... one clue is the comment regarding the pump slide. In a "minimum engine torque" state the pump slide is partially covering the pump intake port. (that is gross minimalization of what is happening, but is accurate) That will explain why the engine is turned off during the pressure test. Based on this scenario I would remove and dissasemble the pump for inspection.
Several components can cause a low pressure or low pressure rise condition.... PCS and related electrical harness, Stuck pressure regulator valve, pressure relief ball and sticking pump slide are what comes to mind.
Hope that helps.
g
Several components can cause a low pressure or low pressure rise condition.... PCS and related electrical harness, Stuck pressure regulator valve, pressure relief ball and sticking pump slide are what comes to mind.
Hope that helps.
g
