1999 Suburban only has reverse

[akersa]

I have a 1999 suburban that has lost all forward gears but reverse still works normal. The other day I was driving and felt a sudden jerk, and then it went back to normal 3 or so miles later i pulled up to a stop light and stopped when it turned green I tried to move forward and it wouldn't in any gear, but reverse worked. I was able to get it backed up on a trailer and when i got it home I checked the codes and I had a P0740 Torque converter clutch solenoid circuit / open, and a P1860 torque converter Pulse Width Modulation Solenoid Circuit. I reset the codes and it is still the same no forward, but reverse works. I have read that ignition switches can cause problems sometimes, but i have never had the instrument cluster go out which seems to be a sign the ignition switch is failing. Any help you could give would be great. I am having bad luck lately and getting this fixed would certainly help me out.

Thanks,

 

[zora]

Did you drop the pan and check if the pan has lots of metal in it?

 

[akersa]

I haven't dropped the pan yet. That is my next step, but the dipstick looked and smelled normal. So i am hopefully that i wont find a bunch of metal in the pan.

 

[Chuzz]

I'm not familiar with GM transmissions at all, but I'd check all of the electrical connections and wires going to them if it were mine. Maybe you'll luck out and find either a loose plug connector or broken wire. Are these transmissions electronically controlled or hydraulic?