From what I understand there's usually warning signs that a pump is failing (MIL code, overheating, poor shifting, noise). They aren't known to fail suddenly like this.

The trans functioned perfectly up until the moment this happened.

I was heading up a (aprox) 15% grade approaching a sharp corner. Probably doing 10-15mph. No noise, no warning. It was like I had shifted it into neutral.

Thought: If the trans attempted to shift into 1st (Slowing for the corner) and the LR solenoid didn't actuate could it cause the same symptom?

A faulty tc control valve won't produce my symptoms. If stuck closed it'll affect gas milage and cause overheating. Stuck open will cause the engine to stall when coming to a stop. It should also generate a MIL code.

The drivetrain appears to be ok.

I'm trying to avoid dropping the trans if possible. I'm pushing 60 so working on cars isn't as easy as it used to be. Working in a driveway of 3/4" drain rock doesn't help either.

I also need to get it back on the road quickly.

I figure it's worth gambling $150 on a solenoid pack. I already have it apart. If that doesn't take care or it the next step will be to drop the trans.

With it out I might as well do a complete rebuild. I've rebuilt 727s and these look (from the tear down videos I've watched) a lot simpler.