Engine/Transmission (1998.5 - 2002) converter not unlocking

[clong]

I have a problem that has cropped up. My auto transmission upshifts fine. But when slowing down it is not unlocking the torque converter until below 40 miles per hour in OD. This is just under 1000 rpm. It just started it today. Any ideas?

 

[inarush76]

L/U

How long since last service? Is fluid level full? Next would be determine if tcc signal is shut off on closed throttle, if so then it becomes possible sticky or restricted tcc solenoid, sticky tcc shift valve in valvebody, or possibly restriction in cooler system. There are a few more possibilities internal,but lets not worry about them at this point. If signal not shut off at closed throttle, it may be problem in pcm or Apps or it's linkage. Email me your # and I'll give you a call and see if I can help.



James

DTT builder/installer

 

[clong]

Fluid level is full. Last service at 120K, truck now has 138K. Serviced every 30K. And I know enough about transmissions to check the fluid and otherwise leave it alone.