I was driving at about 45mph and I heard a "clunk" sound and my transmission disengaged. None of the gears work. It is a 00' Silverado 1/2 ton 4x4 and has 180k. Transmission was rebuilt at 145k and everything was replaced except the torque converter. I can see the transmission switch gears so the cable has not snapped. When I turn on the ignition before I start the truck I hear a grinding noise for 3-4 seconds. Could this be the torque converter or a solenoid? Please help!

Thanks

 

what happens in 4wd

 

Nothing. I can switch to any gear and the truck will not move. It revs the engine like it is in neutral.

 

drop the tranny and start looking.

 

do you have reverse if so the forward sprag came apart, that what it sounds like to me